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In the present study, the phenological and genetic differences/similarities of 95 walnut genotypes were considered. These genotypes had been propagated sexually from the open pollination of the maternal cultivar ‘Maras 12’. This study examined the timing of several phenological features like bud break, leafing, yellowing of the leaves and defoliation in the mother plant and in its progenies. A total of 6 ISSR primers were used for determining genetic differences among the genotypes. The differences between the maternal cultivar and the offspring genotypes included a difference of 97.89% in the bud-break date, 96.84% in the leafing date, 100% in the yellowing date of the leaves and 94.73% in the defoliation date. On average, the phenological variation stood at 97.36%. PCA analysis also confirmed the presence of genetic diversity-based phenological markers in our walnut seedling collection with PC1 58.27%, PC2 27.16%, PC3 12.16%, and PC4 2.40% of the total variation. A total of 38 bands were obtained in molecular analyses. These bands were largely polymorphic (89.47%). While the average number of alleles was 5.66, Polymorphism Information Content (PIC) varied between genotypes from 0.47 to 0.95, and the average PIC value was 0.64. The UPGMA dendrogram divided the genotypes into two main clusters and the similarity coefficient of the genotypes varied between 0.68 and 0.96. In sum, it was found that open-pollinated walnut genotypes had high degrees of phenotypic and genetic variation in comparison with their maternal cultivar ‘Maras 12’.

Breeding for new ornamental varieties is quite often a profitable occupation in the world. Worldwide breeding activities have generated a massive amount of literature. All present day ornamental varieties have evolved through bud sports, open pollinated interspecific crosses, open pollinated intraspecific crosses, planned crosses, natural chromosomal changes, chromosomal manipulations, induced mutations and using new breeding techniques like management of chimera, in vitro mutation, molecular approaches, somaclonal variations etc. The breeders have modified and improved these techniques on need basis to achieve targeted and directional changes. All work on ornamental breeding and development of new varieties are the results of concerted efforts of scientific community, nurserymen, breeders, amateur growers and flower lovers. It is important to highlight the factual account of the early work, genuine drawback of fulfillments and success of ornamental breeding. It is now needful to assess the present status of each technology developed after extensive research activities conducted by different research institutions. Breeders will be familier with the capability and constraints of different techniques and select the proper experimental approach which is most suitable and profitable to achieve their goals. This review provides an indeepth knowledge base for accurate designing of future breeding strategies in the field of ornamentals. The entire breeding system of ornamentals have been very simply reviewed and cited with very common examples so that even a new breeder can follow and select the most suitable techniques for developing the new varieties with desired traits of commercial ornamental species.

The presence of residual female fertility in most of the parthenocarpic banana accessions encourages the banana breeder to develop new hybrids through conventional breeding. Desirable trait can be fixed in the first generation of hybrid progenies, but the evaluation of these hybrids in field is the time-consuming process owing to non-availability of uniform suckers/planting material. This can be overcome by developing multiple shoots from single embryo in a short period of time through embryo culture. A protocol for in vitro multiplication of plantlets from zygotic embryos was standardized in seeded accessions. Multiple shoots from zygotic embryos were achieved up to 55.2% and 64.1% in seeded accessions of Musa acuminata and M. velutina respectively in medium supplemented with 17.76 µM of BAP. The Single shoot derived (only germination) from zygotic embryos was decapitated and the apical meristem were disturbed for further multiple shoot formation in media supplemented with 17.76 µM of BAP. Present studies revealed that in total 75% and 91% of the M. acuminata and M.velutina embryos were able to produce multiple shoot from single embryo by manipulating the media composition and decortications technique. The above protocol was applied for zygotic embryos obtained from controlled pollination (18 cross combinations) and open pollination (nine accessions) of various genomic groups (ABB, AAB, AA). The multiple shoots derived from zygotic embryos and plantlet germinated from zygotic embryos was examined for genetic fidelity analysis by SSR markers. The protocol for multiple shoot formation from single zygotic embryo under in vitro culture developed in this study will accelerate the banana breeding program.

Male sterility is a useful trait in traditional and hybrid wheat breeding. A dwarf male-sterile wheat line that harbors two tightly linked dominant traits, one, the dwarf gene Rht-D1c (originally called Rht10), and the other, the male-sterility gene Ms2 (the two genes linkage group is collectively called RMs2), has been widely used in wheat breeding programs in China. The dominant Ms2 (or RMs2) locus confers complete male sterility in wheat. In this study, we compared the plant height and spike traits in the Ms2 (or RMs2)-isogenic BC2F1 lines that were derived from four soft white winter (SWW) wheat of the US Pacific Northwest (PNW), and the SWW line ‘Brundage’ that harbored an Ms2 transgene. The dominant Ms2 gene had no essential effects on agronomic traits, including plant height, spikelet length and spikelet numbers per spike, in the BC2F1 plants of SWW wheats and the T2 transgenic ‘Brundage’. In an open pollination environment in field, the Ms2-positive BC2F1 plants had a 79% natural seed-setting rate, but the RMs2-positive BC2F1 plants had only a 60% natural seed-setting rate, suggesting that the Ms2 system is more practical for cross-pollination than the RMs2 one. This difference is probably due to the extreme plant height-reducing effect (45% reduction on average) and the late anthesis effect (3–5 days in general) of the Rht-D1c locus. Collectively, these investigations showed that the dominant Ms2 gene has no detrimental effects on plant and spike growth in five PNW wheat varieties/lines, therefore can become a valuable gene tool for traditional and hybrid breeding in wheat.

The potential of an alien plant to spread rapidly and colonize new habitat may be related to the mode of reproduction and the ability to attract pollinators. Most studies focus on widespread invasive plants, in which pollinators are rarely limiting. Here, we assess the ability of a recent invader in South Africa, the tristylous Lythrum salicaria to self-reproduce and whether this can explain the delay between introduction and spread. This study was conducted in one of the largest known populations (a total of 7 populations in South Africa) of L. salicaria in the Liesbeek river in the fynbos biome. We assessed the importance of pollinators and autonomous selfing in L. salicaria by comparing seed set between pollinator excluded and naturally pollinated flowers. Overall, 5 pollinators (4 native and 1 alien) were recorded with Cape honeybees and Africa Monarch butterflies the most prominent. Seed and fruit set were significantly higher in open pollinated flowers compared to pollinator excluded flowers. Also, seed and fruit set in pollinator excluded flowers were higher in long and medium morphs compared to short morphs. Germination was high for seeds from pollinator, but also from pollinator excluded treatments. This shows that L. salicaria in South Africa is self-compatible to some extent, but it is frequented by pollinators, significantly increasing seed production. Despite L. salicaria being tristylous, all 3 morphs are present in South Africa and with a huge seed production, this species has the potential to become a major invader of rivers and wetlands in South Africa.

Alfalfa (Medicago sativa), known as green gold, is one of the best-known forage plants in the world. Alfalfa is an autotetraploid allogamous plant with a large genetic diversity among its cultivars. This diversity is due to self-incompatibility, a high rate of allogamy, and open pollination. This study aimed to investigate the biodiversity of grain storage proteins of M. sativa using gel electrophoresis. For this purpose, seed proteins of 12 Iranian genotypes including seeds collected from Lenjan of Isfahan, Dashte Qazvin, Asadabad, Qasr Shirin, Taleghan Qazvin, Malayer, Isfahan, Saqez, Gonbad Kavous, Kamyaran, Shiraz, and Najafabad of Isfahan were studied and a total of 22 strips were identified. Then, the strips were used to estimate the genetic distance of alfalfa genotypes. The results of the study based on the presence and absence of specific protein bands in the seed protein pattern showed that genotypes 1 (Collection from Isfahan-Lenjan) and 12 (Collection from Najafabad-Isfahan) have the most variation. A similarity matrix was calculated and cluster analysis was performed based on the Jaccard similarity coefficient by the UPGMA method. The similarity coefficients ranged from 0.3 to 1. In general, classification based on cluster analysis showed a similar trend to the differences observed in gel electrophoresis. The total protein of population number 12 (Najafabad population of Isfahan) had the highest amount among the studied genotypes. The highest and lowest number of bands were related to genotype number 12 (population of Najafabad, Isfahan) and genotype number 11 (population collected from Shiraz), respectively. Therefore, the results showed that the protein pattern of alfalfa seeds based on the presence and absence of protein bands can determine genetic diversity. These findings can be used in future research in the field of proteomics and breeding studies in future.

Self-incompatibility, low yield and fruit set represent important factors influencing the pear production in Iran. Some compounds such as polyamines and the mixture of some mineral elements like SICS could be suitable to decrease above concerns. The trail included putrescine (Put) (0.1, 0.25 mM), both spermine (Spm) and spermidine (Spd) (0.05, 0.25 mM) and SICS (1, 2 mg/L) in (self and open) pollination and control. Spd (0.25 mM) in open pollination mode showed the highest yield per branch and fruit set in comparison with control. Spermidine (0.25 mM) in self-pollination mode was the best treatment for fruit length and diameter. In self-pollination mode, Spd (0.05 mM), Spm (0.25 mM) and SICS at 2 mg.L showed the significantly increase in irregular fruit shape. Spd and Put (0.25 mM) in self-pollination showed the best fruit volume among all of the treatments at both of pollination mode

The objective of this study was to compare the evolution of two populations of opaque-2 and purple maize in the central semiarid region of Argentina, and to characterize the agronomic traits and grain chemical attributes to conclude the varietal description of each population. Introduced germplasm of both varietal types was grown under rainfed conditions during four crop years (2011/12, 2013/14, 2014/15 and 2015/16) and characterized both agronomically and chemically. Significant differences were observed between varietal types in the morphological traits of plants and cobs, but did not differ in male flowering or female flowering. Purple maize exhibited taller plants with thicker stems and smaller cobs with heavier grains than opaque-2 maize. Purple maize showed lower grain yields (mean of 4.84 vs. 6.16 tn ha−1 in opaque-2 maize) with more marked variations between cycles (3.02 to 6.62 vs. 5.47 to 7.28 tn ha−1 in opaque-2 maize). The effects of the environment and genotype x environment interaction (G × E) were more notable for grain yield and grain chemical features such us protein, amylose and phenolic compound contents. Nonetheless, most of the agronomic traits in each varietal type showed higher genetic effects (67–92% in opaque-2 maize and 55–82% in purple maize) and a lower G × E (3–14% in opaque-2 maize and 7–19% in purple maize). The advances of this study represent substantial efforts on the development, characterization and description of maize genetic resources in Argentina, which represent potential raw materials for the functional-foods industry.

Although maize being the second most important staple crop of Nepal after rice in term of area and production, its productivity is very low as compared to other develop nation. Unavailability of location specific maize hybrids might be one of the major causes of low productivity. Hybrid yields 20–30% more than open pollinated variety. National Maize Research Program (NMRP), Rampur, has registered and released seven maize hybrids but they are not suitable for all agro-climatic region of Nepal. This paper was prepared after intensive review of all the information obtained from all available resources i.e. journal article, NMRP and Nepal Agriculture Research Council (NARC) annual report, book, proceeding as well as electronic sources. Hybrid maize covers only 10% of total maize area of Nepal. High price of hybrid seed, a wide gap in anthesis-silking interval, poor seed set, difficulties in early generation lines, untimely availability of inputs (irrigation, fertilizer, pesticides etc.), requirement for seed replacement in every season and high irrigation are the major problems associated with hybrid maize cultivation in Nepal. So, in order to increase the productivity of hybrid maize which will ultimately raise the economic standard of farmers, the emphasis must be given on hybrid maize research and development that suit to all agro-climatic region of Nepal.

Grewia flavescens Juss. is an underutilised fruit species found throughout semi-arid and sub-humid parts of the world including India. For the first time, an attempt was made to study the role of different flower visitors on fruit set of G. flavescens. We have recorded different floral visitors, activity patterns, foraging behavior and their role in fruit set. A total of 25 species of floral visitors were recorded, of which Megachilidae (48.35%) was the most abundant group followed by Apidae (27.21%), Halictidae (10.29%) and others (14.15%). Among floral visitors, the foraging rate and foraging speed of Megachile and Xylocopa were studied. They were also effective in depositing more pollen on the stigmatic surface per visit than other flower visitors. Fruit-set was higher (71.42%) in open pollinated flowers than in artificial-cross pollinated (68.33%). Whereas, artificially-selfed and pollinator excluded flowers resulted in the lowest fruit-set (22.22% and 8.95%, respectively). G. flavescens is a self-compatible species but favouring cross pollination and also exhibited delayed self pollination to ensure reproductive success in the absence of an effective pollinator.

In this research, ‘Pedro’ walnut variety (maternal parent) was open pollinated. Offspring genotypes were compared with their maternal parent in terms of morphological and molecular features. Leafing and leaf fall dates were measured as two phenological traits. Genetic differences were identified by molecular fingerprinting using twelve Inter Simple Repetitive Sequence Polymorphism (ISSR) primers. In some progenies, leafing and leaf fall occurred later than the maternal parent (‘Pedro’). Progenies were grouped according to their similarities with the maternal parent regarding leafing date. Specifically, 14.44% of the progenies were ‘Very close’ to the parent, 16.66% were ‘Close’, 30.00% ‘Far’ and 38.89% ‘Very far’. Regarding the leaf fall date, 7.78% of the progenies were ‘Very close’ to the parent, 28.88% were ‘Close’, 36.66% ‘Far’ and 26.67% ‘Very far’. A total of 43 bands were obtained in molecular analyses. These bands were largely polymorphic (95.34%). The average number of the alleles was 3.90, while the polymorphism information content varied between 0.14 and 0.91 among the genotypes. Genetic distances were tested according to the UPGMA (Unweighted Pair Group Method with Arithmetic Average) and by The Structure Analysis. The UPGMA dendrogram divided the genotypes into two main clusters and the similarity coefficient of the genotypes varied between 0.61 and 0.99. This study revealed that ‘Pedro’ can be used as an excellent parental variety in hybridization programs which prioritize late-leafing in walnut breeding. Furthermore, ISSR primers can be safely used for fingerprinting walnuts in general.

The fall armyworm (FAW) is a gregarious insect pest causing substantial yield losses and crop failures in maize and related cereal crops in sub-Saharan Africa due to a lack of resistant varieties and integrated control options. Genetic variation for economic traits including resistance to the FAW damage is a prerequisite in maize improvement programs. The objective of this study was to determine the genetic diversity of 59 maize genotypes of diverse genetic background with variable resistance to fall armyworm, using phenotypic traits and SNP-based DArT markers. The test genotypes were profiled using agro-morphological traits, FAW damage parameters, and Diversity Array Technology Sequencing-derived single nucleotide polymorphism (SNP) markers. Significant (p

Valeriana wallichii DC. (Valerianaceae), a threatened medicinal plant of Himalayan region, has individuals showing 3 patterns of sex expression (female, hermaphrodite, and gynomonoecious). In the present study, the effect of floral size reduction on pollination efficiency of female flowers on female plants of Valeriana wallichii has been determined. To check entomophily as the possible mode of pollination, plants growing in nature are monitored whether or not the flowers are visited by some insects. Apis dorsata and Apis cerana are observed to be the main pollinators of this species. Female plants receive less pollinator service as compared to hermaphrodite plants. Reduced floral size in females offers more number of stigmas to get pollinated in a single visit as greater number of flowers get in contact with the visiting insect. The time of stigma receptivity also varies in female and hermaphrodite flowers. In females, it remains receptive for longer duration. Further, the pollen load on stigmata of open pollinated hermaphrodite as well as female flowers is studied. It is experimentally demonstrated that at the end of the season, the amount of pollen load is lesser in females as compared to hermaphrodites. Reproductive output of both types of individuals is estimated, and seed germination experiments are performed. Reproductive output and seed germination are more in females.

Pollination specialists are increasingly threatened worldwide, especially in intensively-managed durian orchards where loss of pollinators may lead to reduced fruit production. In tropical plant communities where plant species attract multiple species of pollinators, specialists may have advantages over generalists. The present study examined the pollination ecology of durian (Durio zibethinus) in intensively and non-intensively managed orchards in suburban habitats of Nakhon Nayok and Chanthaburi provinces, respectively, in Thailand. Manual-pollination yielded the greatest fruit set 60 d after pollination, followed by open pollination (mostly by pteropodid bats), and insect pollination, while non-pollinated flowers had no fruit set. Eonycteris spelaea was the major bat pollinator in both provinces. Bats found in suburban habitat of Nakhon Nayok were mostly Eonycteris spelaea (67%). Pollen of at least five plant species was found on Eonycteris spelaea fur, including Musa sp., Oroxylum indicum, Durio zibethinus, Bombax valetonii and an unknown species. Pollen of only two species, Oroxylum indicum and Musa sp., was observed on Cynopterus sphinx fur. The non-intensive orchards in Nakhon Nayok, where mixed-species gardens are maintained under more naturalistic conditions, might offer higher fruit set on average. Such conditions might maintain higher bats capture rate of natural pollinators and reduce the risk of pollination failure in comparison with intensively-managed durian orchards.

Introduced plants become decoupled from their usual pollinators and by relying on resident pollinator species or other reproductive strategies become established in new areas, spread and, eventually, invade. Here, using breeding system experiments, we studied the reproductive biology of the bird-pollinated South American species Nicotiana glauca across native and non-native areas, both inside and outside the range of flower-visiting birds. In the native range, where the species is visited by hummingbirds, open cross-pollinated flowers set as many seeds and almost as many fruits as open pollination controls, suggesting that pollinators make a major contribution to reproductive success. In South Africa, the flowers were pollinated by sunbirds which, although less efficiently, also contributed to N. glauca reproduction, replacing hummingbirds. In contrast, in Mallorca, where nectar feeding birds are absent, fruit production in open cross-pollinated flowers was near zero, and significantly lower than in open pollination controls, suggesting that reproduction is almost entirely by autonomous self-pollination. Hand-pollination experiments showed that the species is self-compatible throughout its range. Pollinator exclusion experiment showed that N. glauca relies on self-pollination only in pollinator poor areas, where plants have a much higher capacity for autonomous self-pollination than elsewhere. A reduction in anther-stigma distance does not seem to account the higher self-pollination capacity in the non-native environment without pollinators. Despite probable evolutionary adaptation, and flexibility in pollinator association and mating system, seed production in the introduced range was somewhat pollen limited, suggesting that the mismatch between N. glauca and its novel pollination environment might retard invasion., Funding for this research was provided by the National Research Council of Argentina (CONICET), the National Ministry of Science and Technology of Argentina, the Department of Science and Technology of South Africa and the Spanish Research Council (CSIC).

Polyamines and SICS (Manganese + Boron) are popular chemical compounds using for the improvement of qualitative traits of pear and apple fruits. In the present study, we investigated the effects of these compounds on self- and open-pollinated shoots of pear trees. Treatments included putrescine (Put) (0.1 and 0.25 mM), Spermine (Spm) and Spermidine (Spd) (0.05 and 0.25 mM), and SICS (1 and 2 mg/L) solely or along with coverage cotton bags (CCB) in order to prevent cross and open pollination. Based on the results, treatment of Put (0.1 mM) alone showed the highest oxidative material index (P

Genetic variation provides the foundation for species to survive, reproduce and evolve. Wolf trees are an example that may have a difference genetic background; however, research on the genetics of Scots pine (Pinus sylvestris L.) wolf trees is limited. The objectives were to assess (1) the morphological and genetic differentiation of wolf tree morphotypes in artificially established young commercial Scots pine stands using chloroplast microsatellite (cpSSR) DNA markers; and (2) the genetic differentiation based on progeny testing of mature wolf tree and regular tree morphotypes found in natural Scots pine stands. Our material consisted of (a) a 20-year-old artificially established stand in central Lithuania, where we morphotyped all trees and genotyped 59 wolf trees and 50 control trees at 6 cpSSR loci, (b) a nursery test where we assessed the morphology of 2-year-old open pollinated progeny of 8 wolf trees (20 seedlings per tree) in comparison with a control selected in a mature stand in northwestern Lithuania. Results showed a significant genetic differentiation between wolf trees and regular trees in young plantations based on the cpSSR DNA markers. Wolf trees had a higher genetic diversity at the cpSSR loci compared to the regular trees in the young plantations. The progeny test showed wolf trees contained more lateral shoots and possessed larger crown at age 2 in the nursery test. Our study suggests that there is a genetic background for the morphological differentiation between wolf trees and regular commercial Scots pine trees. However, the morphotype structure of wolf trees is complex, thus requiring future replicated studies spread across different regions and age classes.

The morphological characterization allows one to estimate and evaluate the genetic distance among different varieties, identifying heterotrophic groups by means of clustering methods. The objectives of the study were to characterize improved open-pollinated varieties (VPAs) and maize landraces based on the main quantitative agronomic traits and to estimate the variability and similarity between them. Sixteen maize varieties from the southern region of the State of Rio Grande do Sul, Brazil were evaluated. Data were subjected to analysis of variance. For the characterization, the Tukey averages comparison test was performed. The similarity among the varieties was tested using the Tocher optimization method. The differences detected indicate the presence of genetic variability among the studied varieties. According to the Tocher grouping, it was found that some populations have the potential to be selected as parents in breeding programs, maximizing the variability obtained from their crosses. For certain traits, maize landraces do not differ from improved varieties and show high similarity.

Fertility experiments were carried out on a plantation of haskap berries (40 cultivars) in southern Poland. Based on the observation of phenological phases, the cultivars were divided into three groups with similar overlapping periods of full flowering: the earliest comprising 11 cultivars; the moderate-early, 17 cultivars; and the latest, 7 cultivars. The attractiveness of cultivars for pollinating insects was evaluated on the basis of flower biometric measurements. Flowers are more diverse in length than in width of the sympetalous corolla, with the pistil always being longer than the corolla, which is conducive to effective insect pollination. A pollen viability coloring test and germination capacity on agar medium were used to assess pollen quality. Despite very high pollen viability (on average, 90%), the percentage of germinating pollen was very low and ranged from 3.3 to 34.5%. Pollen yields for each cultivar were calculated based on the number of pollen grains in the flowers. The cultivars differed significantly in terms of the number of pollen grains in the flowers. The cultivar “Morena” was characterized by the highest number of pollen grains (45,375), while the cultivar “Fialka” had the lowest (2750). Microscopic observations of pollen tube overgrowth through the style of the pistil after open pollination and self-pollination allowed for calculation of the pollen germination index (PGI) used to assess the fertility of the cultivars. Self-pollinated cultivars with a PGI 2, which proves the self-fertility tendency of this cultivar.

Genetic diversity among breeding populations is key in plant breeding programs. This study aimed to determine the extent of genetic diversity among 37 diverse maize genotypes using simple sequence repeat (SSR) markers. The maize genotypes were selected based on their variable resistance to Striga asiatica. Maize genotypes were fingerprinted using 18 polymorphic SSR markers. Marker and population diversity parameters were computed. A total of 191 alleles were detected and the number of effective alleles varied from 2 to 21 per locus with a mean of 11. The polymorphic information content (PIC) of the SSR markers varied from 0.59 to 0.96, with a mean of 0.80. Significant differences were observed among populations, individuals and within individuals. Within and among individual variances accounted for 85% and 13% of the total gene diversity. The genotypes were grouped into three main genetic clusters, which were not influenced by genotype origin. Mean genetic distance (0.43) and low geneflow (0.18) were observed among the populations. High mean genetic identity (0.65) was recorded, indicating potential genetic ‘bottleneck’ among the selected germplasm. The following open pollinated varieties; Border King, Colorado, CIMMYT’s ZM OPVs, Mac Pearl, Shesha, Nel Choice, Natal 8Lines, Nel Choice QPM, Hickory King, Kep Select, Obatanpa and the Striga resistant synthetic variety DSTRYSYN15 were selected from different clusters for breeding.

Molecular-based characterization of open-pollinated varieties (OPVs) in maize is useful to define their unique profiles. A total of 58 SSR markers selected from a panel of 70 were used for genotyping three samples of 30, 50 and 100 plant bulks for each of 32 OPVs. The SSR markers detected a total of 253 alleles in the 32 maize OPVs across the three bulk samples. The number of alleles per marker varied from 2 to 7, with an overall mean of 4.36. The genetic distance among the OPVs varied from 0.17 to 0.93 with an average of 0.70 ± 0.007 for bulk samples of 30 plants, 0.20 to 0.91 with an overall mean of 0.70 ± 0.007 for bulk samples of 50 plants and from 0.30 to 0.95 with an average of 0.75 ± 0.006 for bulk samples of 100 plants. Cluster analysis separated the 32 maize OPVs into two major groups, which were further separated into two sub-groups for each type of bulk sample. The groupings of the OPVs into two major groups and their corresponding sub-groups was consistent with known breeding history (common parentage) and common target traits during development of the OPVs irrespective of the sample size used. However, in the bulk samples of 50 and 100 plants, some sub-groups were composed of OPVs with mixed maturity classes and diverse genetic backgrounds. Of the three independent bulk samples, the smallest sample size of 30 plants was found to be optimal for characterizing heterogeneous and heterozygous maize populations and OPVs owing to its cost-effectiveness and relative ease of sample processing.

Maize weevil (Sitophilus zeamais Motschulsky) is a common insect pest affecting stored maize (Zea mays L.) worldwide and can be controlled by breeding for host resistance. Information on combining ability and gene effects conditioning maize weevil resistance would be required to devise breeding strategies. However, there are disagreements regarding the seed generation to subject to maize weevil resistance evaluation. This study determined the seed generation effect on the quality of genetic information obtained from a maize diallel cross. Eight weevil-resistant and two susceptible maize inbred lines from eastern and southern Africa were crossed in a 10-parent diallel scheme. The resulting F1 hybrid seed, F2 full-sib grain from controlled pollination, and F2 half-sib grain from open pollination were evaluated for maize weevil resistance and responses were determined using the number of F1 weevil emergence from the seed (FWE), median development period (MDP), Dobie’s index of susceptibility (DIS), and parental weevil mortality (PWM). General combining ability (GCA) and specific combining ability (SCA) effects were significant for the FWE, MDP, and DIS in all seed categories. Results revealed that reciprocal effects were predominant in F1 hybrid seed, GCA effects were predominant in F2 full-sib grain, while SCA effects were more important in the F2 half-sib grain. The F2 full-sib generation exhibited superiority in providing genetic information required for parental line selection when breeding for weevil resistance, compared to F1 hybrid and F2 half-sib grain. Resistant inbred lines MV170 and MV142, produced hybrids that exhibited high levels of maize weevil resistance across all the three seed categories thus, qualifying as suitable materials for breeding weevil resistant maize hybrids.

Passion fruit breeding programs often use a single fruit to obtain progeny. Open-pollination progenies are considered half-siblings since they allow the occurrence of a mixture of pollens during pollination. However, there are no studies able to prove that these progenies are, in fact, consequence of a mixture of pollens. The contribution of male genitors to the formation of open-pollinated progenies and genetic diversity were evaluated by means of microsatellite markers. A hybrid test was performed based on the gathered genotypic data, a chi-square test was used to verify the expected and observed frequencies, and the proportion of identical genes by descent (IBD) was estimated. Genetic diversity was studied through descriptive analysis, cluster analysis, and molecular analysis (AMOVA). The hybrid test indicated the participation of more than one male genitor in progeny formation. However, the genotypic composition observed in the progenies differed significantly from that expected when assuming crosses between all individuals of the origin population. The IBD values for the progenies ranged from 0.26 to 0.30, indicating that they are progenies of half-siblings. The progenies showed observed heterozygosity greater than expected and an inbreeding coefficient close to zero. The AMOVA revealed that the greatest genetic variation (81.96%) occurred within progenies. In sour passion fruit, open-pollinated progenies obtained from a single fruit do not present genotypic composition representative of their population of origin since the greatest genetic diversity was observed within the progenies.

The consequences of recurrent drought events compared with a single drought and its interaction with deliberate selfing, compared with open-pollination on post-stress recovery, persistence, and drought memory, are not understood in orchardgrass (Dactylis glomerata L.). A long term study was started by creating 25 selfed (S1) and 25 open-pollinated progeny of orchardgrass in 2012. Populations were studied in the field, applying a normal and a recurrent drought stress environment for 4 years (2013–2016). In 2016, after the first harvest (June), watering was withheld in both moisture environments for 2 months and then plants were re-watered and evaluated for post-drought recovery and drought memory. On average, open pollination caused higher forage yield in the second and third years; while, in the first and fourth years, there was no significant difference. Obligate selfing reduced persistence of genotypes but did not affect recovery after prolonged drought. The early flowering genotypes had more plant productivity, yield stability, persistence, and drought tolerance, and were also capable of more regrowth and recovery. The results showed that genotypes of orchardgrass constantly performed differently under periodic drought as compared to prolonged drought stress. Moreover, there were significant genetic variations between genotypes in terms of stress memory.

The capacity to produce seed, both by selfing and outcrossing, or mixed mating strategies, is considered a mechanism for overcoming unpredictable pollinator availability. In the present study, we investigate breeding system, insect visitations and the role of insect visitors in the pollination of five species of Oenothera subsect. Oenothera. Field experiments showed that autonomous selfing occurs at bud stage, prior to the opening of the flower. Control flowers showed similar seed set to hand-pollinated flowers, whereas emasculated flowers and those subject to open pollination set fewer seed. These results are consistent with the hypothesis that the investigated Oenothera exhibit a great capacity for autonomous selfing and that selfing is selected in order to provide reproductive assurance. Although flowers were visited mostly by nocturnal lepidopterans, these insects did not precipitate pollination and are thus considered nectar thieves. Conversely, analysis of pollen loads and behavior during foraging by diurnal insect visitors revealed that honeybees and bumblebees are the probable pollinators. We conclude that production of flowers capable of autonomous selfing at bud stage, followed by anthesis and opportunities for outcrossing, probably improves the invasive potential of these Oenothera in Europe, together with a rapid increase in their populations, even when pollinators are scarce.

The nature of genotype–environment (GE) interactions was investigated for two F1 hybrids and eight open pollinated varieties (OPVs) of pearl millet for grain yield in 12 environments spread over 2 years (2010 and 2011) across the pearl millet growing belt of Sudan. The joint regression analysis showed significant linear and non-linear GE interactions corresponding to heterogeneity and remainder mean squares. However, the GE interactions of all genotypes except PGO9PM1 were explained by the linear regression model. Six OPVs and hybrid PGO9PM3 showed general adaptation with b ≈ 1.0 and non-significant remainder mean squares. Of these genotypes, while hybrid PMO9PM3 was the highest yielding (917 kg ha−1) farmers could adopt any genotype by trading off between their desirable traits such as mean grain yield, earliness, fodder yield and quality criteria etc. Two varieties (ISC-III and MCNELC), were specifically adapted to below average environments with their mean grain yields non-significantly different from the other six OPVs. The highest yielding hybrid PMO9PM1, on the other hand, showed specific adaptation to favourable environments but also had large remainder mean squares. More complex models such as quadratic, 2-intersecting-straight lines, 3-intersecting-straight lines were fitted which, however, could not account for the large remainder mean squares. A 3-lines model with quadratic component in the higher yielding segment of environments was found adequate showing that the upper threshold value for the hybrid was not reached and it would continue responding to higher yielding environments.

A protocol is described for somatic embryogenesis (SE) Pinus elliottii × P. caribaea, an interspecific pine hybrid of major economic importance. Different embryogenesis conditions were tested, from time of initiation to plant regeneration. Immature megagametophytes containing zygotic embryos of five open pollinated (OP) mother trees were used for SE initiation. An established rate of 10.2% was achieved for explants inoculated on modified Litvay’s medium (mLV), supplemented with BAP (4.5 µM) and 2,4-D (9 µM). Initiation of SE was influenced by the mother-tree genotype however, modification of culture conditions enabled establishment of embryogenic cell lines (ECLs) from all OP seed families. Fifty-two percent of somatic embryos developed to the cotyledonary stage on mLV, supplemented with 40 µM ABA and 6% w/v sucrose. Cotyledonary stage somatic embryos converted to plants at 45–86%. Four months after acclimatization in a greenhouse, plant survival rates ranged between 78 and 94%. Flow cytometry analysis of ploidy, did not show any variation in ECLs and somatic seedlings.

The opposite modes of chloroplast DNA (cpDNA) inheritance were found to operate in the reciprocal crossings of Scots pine (Pinus sylvestris L.) and mountain dwarf pine (Pinus mugo Turra). The crossings were found to be partially compatible. In P. sylvestris × P. mugo crossing, the paternal transmission of cpDNA to the offspring takes place corroborating the generally acknowledged concept of the paternal cpDNA inheritance in gymnosperms. On the contrary, in P. mugo × P. sylvestris crossing the seed progeny exhibited P. mugo haplotype of the mother tree deviating conspicuously from the above concept. In the open pollination offspring of the putatively hybrid individuals of the Scots and mountain dwarf pines, a biparental inheritance of cpDNA was revealed in mother tree with P. mugo haplotype indicating a loosened control of the maternal inheritance of cpDNA in the putative hybrids. Implications and impacts of this finding for further studies are discussed.

Grewia flavescens is a fruit species found throughout semi-arid and sub-humid parts of the world including India. In contemporary era, emphasis on food supply, market value and medicinal utility of underutilized crops made this fruit species suitable for commercial cultivation. The present study was the first attempt made to study the floral biology of G. flavescens. Anthesis was noticed between 1130 and 1300 h whereas, between 1200 and 1230 h its peak anthesis was observed. Pollen dehiscence occurred 1–2 h prior to anthesis. The maximum pollen viability of 80.34 ± 5.16 per cent with 1% acetocarmine was observed at the time of anthesis and it was coincided with the stigmatic receptivity. After 2 h of anthesis, receptivity of stigma was found maximum and the peak nectar production was between 0 and 2 h after flower opening. A total of 21 flower visitors were recorded, of which Megachile species was more abundant compared to Apis, Xylocopa species and other minor flower visitors. The absence of insect pollination reduce the fruit set 21% from 82% under open pollination. Delayed selfing was observed as a safety mechanism in this species.

Outcrossing rates in biodiesel species Pongamia pinnata were estimated using amplified fragment length polymorphism (AFLP) and microsatellite markers. Five AFLP primer combinations and eight pairs of microsatellite primers were used for fingerprinting of 55 open pollinated progenies derived from five mother trees. The multilocus out-crossing rate was quite high with AFLP (0.917; SD = 0.103) and comparatively low with microsatellite markers (0.748; SD = 0.127). The multilocus out-crossing rate was higher than single locus out-crossing rate in case of both marker systems (tm − ts = 0.203; SD = 0.090) which implies that biparental inbreeding occurred at significant levels. The estimated F was higher than the expected which also indicated towards high inbreeding in the progeny population analyzed. This is the first study on estimation of outcrossing rates using any kind of molecular marker systems in Pongamia. We expect an increasing use of such high throughput PCR-based technologies in mating-system studies in various other tree species.

This study was conducted to determine the long-term performance under two farming systems of Capia pepper, a summer vegetable in high demand, consumed fresh, as paste, dried, or roasted. The trial was conducted for 9 years on certified organic and conventional plots of Ege University, Izmir, Turkey. In both farming systems, pepper was the main summer crop, but the preceding crop varied between the farming systems and over the years. Certified organic seeds and seedlings of Yalova yaglik-28, an open pollinated variety, were used for Capia pepper production. Yields were statistically similar in the conventional (45,217 kg ha−1) and organic (43,645 kg ha−1) systems; however, significant yield variations occurred with respect to the annual conditions. The farming system significantly influenced fruit quality. The average fruit weight was 99.7 g in the conventional plots compared with 88.8 g in the organic. The fruit pericarp was thicker in the organic (5.1 mm) than in the conventionally grown ones (4.5 mm). The L-ascorbic acid content was (73.4 mg 100 g−1) higher in the conventional fruit, whereas the total soluble solids (7.7%) and red pulp color, determined by a chromameter, as a*/b* (2.0), were more pronounced in fruit from the organic plots. The long-term trial showed that organic management helped to improve the soil organic matter content and fruit quality, especially from the perspective of processing.

Breeding methods applied to faba bean are either based on self pollination by developing lines under insect proof cages or based on open pollination by developing lines under natural pollination conditions. The purpose of this research is to compare the performance of pedigree selection method (PSM) as a self pollinated breeding method and recurrent selection methods (RSM) and synthetics as an open pollinated method. Eleven diverse accessions were used to develop in F6 generation 24 lines using PSM, 35 lines using RSM and nine synthetics from 2012 to 2016. The different developed lines were evaluated in two winter cropping seasons (2014/2015) and (2016/2017) in an alpha design with two replications. Significant differences among lines and among breeding methods were obtained for biological and grain yield, days to flowering, days to maturity, branches per plant, pods per plant, hundred seed weight. Synthetic populations had higher yield than RSM lines; whereas RSM lines revealed higher yield performance than PSM lines. Multivariate analysis indicates that most of the variation among different lines developed by different methods is due to variation in number of branches, days to flowering, biological and grain yield. Open pollinated cultivars were found to be more appropriate to increase the yield in farmers’ fields and may play a critical role in conserving wild pollinators, but ensuring optimal yields might require capacity building for farmers concerning wild pollinators.

Black walnut (Juglans nigra L.) nut production stands on the brink of potentially great market expansion that can only be realized with significant genetic and horticultural improvement, such that commercial production becomes feasible. The goal of this study was to incorporate microsatellite/simple sequence repeat (SSR) markers to genotype 11 cultivars and selections, and establish a mapping population from a cross of two cultivars, “Football” × “Sparrow.” Morphology of these two cultivars coupled with phylogenetic analysis supports the notion that a cross between them may yield desirable hybrids. Of the 51 SSR markers amplified, 23 were polymorphic and useful for genotyping. A selection mislabeled as “Mintyle” was definitively identified as “Mintle”; therefore, the number of cultivars was reduced to 10. Furthermore, seven of the 23 markers were used to identify 91 intraspecific hybrids (“Football” × “Sparrow”) resulting from open pollination, thereby establishing the first mapping population of black walnut using SSR markers.

A new epidemic disease caused by the rust fungus Uromycladium acaciae emerged in 2013/2014 causing defoliation, branch, and stem deformations in plantations of Acacia mearnsii (black wattle) in South Africa. This study investigated the level of genetic resistance to the rust fungus Uromycladium acaciae in six progeny tests from two different trial series. A total of 269 open pollinated families of different levels of improvement, ranging from wild selections to fourth cycle generations were included in the study. Families originated from land race subpopulations of South Africa and from Australian provenances. Rust severity was assessed across all the trials at 6 months of age. In the rust screening trials, different measures of rust incidence were assessed at 6, 12, and 17 months, as well as tree height and mirid damage at 12 months. In the progeny trial series, tree height, stem defects, and gummosis were measured at 36 months. Results suggested that rust incidence is under moderate genetic control at the family level. The coefficient of additive genetic variation was large (59.4%) for the disease incidence. The family mean heritability for rust disease was $$ {h}_{fm}^2=0.48\pm 0.16 $$ in the progeny trial series, whereas it was $$ {h}_{fm}^2=0.33\pm 0.06 $$ in the rust screening trials. Among the rust assessment methods, 6-month rust incidence (yes/no) assessment produced higher heritability estimates. With some exceptions, Australian provenances from low altitude sites along the eastern coast of Victoria and the south east coast of New South Wales showed high tolerance to rust, better growth, low gummosis incidence but poor stem form. All the South African sources showed high rust susceptibility and had average or below average growth, gummosis incidence, and stem form. For rust disease improvement, the South African material should be avoided and the best existing Australian families should be used for further breeding. In addition, new seed sources from Australia should be infused to the breeding program in order to increase the genetic diversity while increasing genetic gain for the rust, gummosis, and growth.

Polyploidization causes ‘genomic shock’ at the genetic and epigenetic levels relative to the parental species. However, few studies have compared the genetic and epigenetic alterations during the process of polyploidization by interspecific hybridization in Brassica species. In the present study, the early generations of hexaploid derived from a triploid hybrid between Brassica napus cv. ‘Zhongshuang 9’ and B. oleracea cv. ‘SWU01’ were developed, and used to detect genetic and epigenetic alterations together with triploid and two parental lines using simple sequence repeats (SSRs) and methylation-sensitive amplified polymorphisms (MSAPs). The derived hexaploids had relatively stable karyotype (69.84% euploid chromosome segregation in S0, 100% and 72.7% hexaploid karyotype in S1 and S2, respectively) and good fertility (88.75% ± 5.43% for pollen fertility, 4.68 ± 3.25 seeds/pod for self pollination and 13.55 ± 3.66 seeds/pod for open pollination), but wide morphologic characters. Compared with the parental lines, the triploid exhibited 13.08% new SSR alleles (17 of 130) and up to 26.45% new MSAP alleles (65 of 246), indicating that interspecific hybridization caused genetic and epigenetic alterations. No change in SSRs and 33.74% alterations in MSAP alleles (83/246) was observed between the triploid and hexaploid S0, suggesting chromosome doubling only caused epigenetic alteration. On average of 39.23% ± 5.78% of DNA methylation alterations and 6.35% ± 3.69% of SSR alterations occurred among the S2, S1, and S0 generations. It indicated that genetic alteration was caused by interspecific hybridization and generation descent of hexaploid, whereas epigenetic alteration resulted from interspecific hybridization, chromosome doubling and generation descent. It is interesting to find stronger epigenetic changes than genetic changes brought on during the processes of hexaploidization between B. napus and B. oleracea. It also found the average genetic distance between hexaploid S2 and hexaploid S1 (SSR 0.056 ± 0.029, MSAP 0.337 ± 0.201) was further than that between hexaploid S1 and hexaploid S0 (SSR 0.023 ± 0.009, MSAP 0.178 ± 0.126), suggesting more genetic variance in the hexaploid S2 generations than hexaploid S1.

Background Grape phylloxera (Daktulosphaira vitifoliae Fitch) is a major insect pest that negatively impacts commercial grapevine performance worldwide. Consequently, the use of phylloxera resistant rootstocks is an essential component of vineyard management. However, the majority of commercially available rootstocks used in viticulture production provide limited levels of grape phylloxera resistance, in part due to the adaptation of phylloxera biotypes to different Vitis species. Therefore, there is pressing need to develop new rootstocks better adapted to specific grape growing regions with complete resistance to grape phylloxera biotypes. Results Grapevine rootstock breeding material, including an accession of Vitis cinerea and V. aestivalis, DRX55 ([M. rotundifolia x V. vinifera] x open pollinated) and MS27-31 (M. rotundifolia specific hybrid), provided complete resistance to grape phylloxera in potted plant assays. To map the genetic factor(s) of grape phylloxera resistance, a F1 V. cinerea x V. vinifera Riesling population was screened for resistance. Heritability analysis indicates that the V. cinerea accession contained a single allele referred as RESISTANCE TO DAKTULOSPHAIRA VITIFOLIAE 2 (RDV2) that confers grape phylloxera resistance. Using genetic maps constructed with pseudo-testcross markers for V. cinerea and Riesling, a single phylloxera resistance locus was identified in V. cinerea. After validating SNPs at the RDV2 locus, interval and linkage mapping showed that grape phylloxera resistance mapped to linkage group 14 at position 16.7 cM. Conclusion The mapping of RDV2 and the validation of markers linked to grape phylloxera resistance provides the basis to breed new rootstocks via marker-assisted selection that improve vineyard performance. Electronic supplementary material The online version of this article (10.1186/s12870-018-1590-0) contains supplementary material, which is available to authorized users.

Hybridization experiments among fir (Abies) species contribute to clarification of both crossability and evolutionary relationships of organisms at least from the second half of the nineteenth century. The main aim of our study was to find possible effects of hybridization on survival rate and two growth parameters (height and diameter at the breast height) of fir trees at various levels of complexity in the Czech Republic. We compared (1) pure species consisting of seven fir taxa, (2) open pollinated hybrids comprising of twenty-one hybrid progenies of Greek Fir (A. cephalonica), Cilician Fir (A. cilicica) and Algerian Fir (A. numidica) and (3) artificial complex hybrids of Korean Fir (A. koreana) × (A. cilicica × A. cephalonica). For our analyses, we used combination of so-called traditional statistical methods and spatial modelling. Our results revealed that a higher level of hybridization and introgression may lead to a higher survival rate and furthermore, that neglecting of spatial autocorrelation in randomized complete block design might lead to wrong conclusions—because our analyses on height showed contrasting results between traditional and spatial modelling. The results of this study appear to be a good message for scientists dealing with forest tree breeding and facing a lack of confidence by practice. They might be also a good news for forestry practice, where foresters face high mortality during afforestation, e.g. in extreme environmental conditions. Our study highlighted that neglecting spatial autocorrelation could possibly lead to wrong conclusions in studies of similar spatial scale level.

The flowering mechanism, visiting insect activities, reproductive system, and floral scent composition of Schismatoglottis baangongensis a Northwest Bornean locally endemic limestone-restricted protogynous mesophyte were investigated. Anthesis started at dawn and lasted ca 29 h. Fruit set for open pollination (93 %) and restricted access pollination (88 %) were high. Colocasiomyia (Diptera, Drosophilidae) and Cycreon (Coleoptera, Hydrophilidae) were the main pollinators. Colocasiomyia flies present in much higher numbers than Cycreon beetles individually carried significantly less pollen load. Chaloenus (Chrysomelidae, Galerucinae) was inadvertent pollinators, and Atheta (Coleoptera, Staphylinidae) passive visitors. Pollen transferal between dissimilar insect genera (Colocasiomyia and Chaloenus) is reported for the first time. Low pollen/ovule ratio of S. baangongensis indicated an efficient pollination mechanism. Ester compound class floral odours, especially the dominant compounds 3-butenoic acid, 3-methyl-, methyl ester, were decisive in attracting pollinators. The spadix appendix of S. baangongensis was the main olfactory body although the spathe was detected to release an additional N-containing compound, an indole. An increase in the total amount of floral scent from the pistillate flower zone during pistillate phase of anthesis from Period I (06:00–08:00 h) to Period II (08:00–10:00 h) was postulated to detain insects in the lower chamber of the inflorescence.

Open pollinated maize varieties are one of the best options for farmers who cannot afford the cost of hybrids, cultivating maize in low potential environments and cannot pay for inputs such as fertilizers and pesticides. The experiment was conducted to use farmers’ input and feedback on selection of well-adapted, high-yielding, and disease-tolerant maize varieties. Treatments were arranged incompletely randomized block design with three replications. Gibe-1 was better preferred open pollinated maize variety by famers due its cob length, disease tolerance, good husk cover and yield. Gibe-1 provided the highest grain yield in South Achefer (8.8 t ha-1) and the best performing genotype across environments with grain yield of 7.8 t ha-1. Gibe-1 also had a good reaction to common leaf rust and tercicum leaf blight. GGE biplot analysis classified testing environments in to four mega environments and showed high influence of the environment to grain yield with the contribution of variation 59.59% by the environment, 7.25% by the genotype, and 18.38% by interaction. Gibe-1 was identified as the most ideal open pollinated maize variety which produced the highest mean grain yield and was the most stable. Therefore, Gibe-1 is recommended as a potential open pollinated maize variety for Jabitehinan, South Achefer, and similar agro ecologies.

Medicago ruthenica is a perennial leguminous plant with great economic value for forage production and soil conservation in northern China. Simple sequence repeat (SSR) markers are a major molecular tool for genetic and genomic research that have been extensively developed and used in major crops. However, few are available in M. ruthenica, an important cool-season forage species in China. Using transcriptome data, we developed 213 polymorphic SSR markers. Additionally, we used these markers to quantify selfing and outcrossing rates of M. ruthenica plants under field conditions. The outcrossing rate was calculated to be 75.9%. The first large set of codominant markers developed for M. ruthenica and knowledge of its outcrossing behavior should be highly valuable for molecular and traditional biological research.

Oilseed rape (Brassica napus L.) reacts differently to foliar application of sulfur (S) and boron (B), and for that reason it is important to find an early indicator that would inform about the direction of this reaction. This study aimed at evaluating the early response of two double-low cultivars of winter oilseed rape: hybrid (Nelson) and open pollinated (Digger) on the foliar fertilization with S and B in two terms: fall and spring, based on the rate of leaf greenness index (SPAD) and seven indicators of chlorophyll a fluorescence (FL). On 7th or 9th day after the application of liquid fertilizers, the selected parameters of FL and SPAD were determined on the leaves of rape. As a result, a significant effect of foliar B and S supplementation on the yield of oilseed rape was found. Principal component analysis (PCA) allowed for a separation for each of the cultivars the two parameters of FL, namely Tfm and Fv/F0, which are sensitive indicators of a physiological state of the rape plants shortly after foliar S and B dressing.

Polyploid breeding offers the possibility of increased variability in the search for improved growth, site adaptation and disease resistance in tropical acacias. A key focus of breeding in Vietnam has been the production and testing of vigorous triploid clones which are expected to have the added advantage of being sterile. Triploids obtained by manual crosses between diploid and tetraploid trees or by bulk screening of seedlings derived from open-pollinated seedlots were verified using flow cytometry. Thirteen clones are under field testing for growth rate, tree form and fertility. Six of these are now reproductively mature and flowered as prolifically as diploids. However no pollen germinated, either on agar or on their own stigmas under controlled pollination. Only one clone (X01—F1 hybrid of tetraploid A. mangium and diploid A. auriculiformis) produced open pollinated pods on 0.05% of hermaphrodite flowers and these contained an average of 1.3 filled seeds per pod, about one-fifth the number observed in diploids. Less than 25% of germinated progeny from this triploid clone survived at 3 months after sowing and survivors were severely stunted with arrested growth. Ploidy and genotype analysis revealed them to be predominantly aneuploids, ranging from hyperdiploid to hypotetraploid with 95% being selfs. We are confident that we can select triploid clones which will be effectively infertile if deployed in plantations and may be of particular value in situations where the normal prolific natural regeneration of tropical acacias is highly undesirable.

Planting various hybrids of larch species in commercial forestry has gained increased importance around the world. However, there are uncertainties about the genetic purity of hybrid larch seed lots due to mixture of pure and hybrid seeds in the outputs of commercial hybrid larch seed orchards. Thus, the aim of the study was to evaluate the feasibility of visible + near infrared (Vis + NIR) spectroscopy to distinguish European × Japanese larch (Larix × eurolepis) from pure European (Larix decidua) and Japanese (Larix kaempferi) larch seeds. Vis + NIR reflectance spectra were obtained using single seeds, and discriminant models were developed with partial-least square-discriminant analysis (PLS-DA) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) on both raw and pre-treated spectra. The best PLS-DA model assigned L. × eurolepis and L. decidua seeds to their respective classes with 100 % accuracy while that of L. kaempferi with 97 % accuracy. The best OPLS-DA model resulted in 100 % classification accuracy of pure and hybrid larch seeds. The origins of spectral differences between pure and hybrid larch seeds were attributed to differences in color, seed moisture content, fatty acids and proteins. In conclusion, the result demonstrates the feasibility of Vis + NIR spectroscopy as a powerful non-destructive method for verification of hybrid larch seeds, which is of great importance in maintaining the genetic purity of hybrid seed lots and for monitoring natural hybridization in commercial open pollinated mixed species seed orchard.

Pearl millet [Pennisetum glaucum (L.) R. Br.] open-pollinated varieties, which are the predominant cultivars, have never been systematically evaluated for adaptation to low-soil phosphorus (P), a major constraint on pearl millet production in West Africa (WA). We evaluated grain yield (GY), flowering time (FLO), harvest index (HI), and residual grain yields (RGY) of 102 open-pollinated varieties from WA under low-P (−P) and high-P (+P) field conditions in six environments of WA. In addition, PE-related traits of the varieties were evaluated at early growth stage in a pot experiment. Significant genetic variation was observed for GY, FLO, HI and PE-related traits. P-efficient varieties had higher yield under −P conditions. Varietal performance under −P varied across environments depending on FLO, relative flowering delay under −P (FD) and RGY measured in the field. Low-P-susceptible varieties had higher FLO, lower HI than low-P-tolerant varieties. Response to direct selection under −P field conditions was 20.1 g m−2, whereas indirect selection response under +P was 16.3 g m−2. Selection under −P field conditions while taking into account seasonal variations for FLO, FD and PE is expected to be important for improving GY specifically targeting −P environments in WA.

We applied a series of intra- and interspecific in situ cross-pollination experiments under greenhouse conditions to evaluate the breeding systems in four Fosterella species (Pitcairnioideae s.str.; Bromeliaceae). Viable hybrids were produced between each pair of the investigated species, suggesting that reproduction barriers may be low also under natural conditions. Seed germination rates proved to be high in each crossing treatment, indicating a high viability of the artificial hybrids. Large numbers of seeds were produced after both closed and open pollination treatments, suggesting that autogamy may be a major reproductive strategy in the genus. Our results support the concept that self-compatibility is an appropriate way to avoid natural hybridization in Bromeliaceae and could assist in maintaining species integrity in the presence of pollen flow. Paternity was verified in all crosses by genotyping parents and offspring with a set of polymorphic nuclear microsatellite markers. To study the mode of chloroplast inheritance, we developed a novel set of 24 chloroplast microsatellite markers using 454 pyrosequencing technology, and applied four of these markers for genotyping parents and offspring from all crosses. Our results clearly demonstrated a maternal inheritance of plastids.

Three wild populations of Artemisia glauca Pall. ex Willd. occurring in the Pir Panjal mountain ranges and in the Kishtwar Himalayas of Jammu and Kashmir State, India, have been analysed for their meiotic systems and reproductive output. Of the three, two namely Poonch and Rajouri populations have a chromosome count of 2n = 18, while the third population named as Kishtwar population has 2n = 36. These are in all probability diploid and tetraploid cytotypes. While the tetraploid Kishtwar population shows stunted growth, diploid ones show little variation at the morphological level but display prominent interpopulation differences in detail of chromosome size and chiasmata frequency. Meiotically Poonch population is more stable than Rajouri. The differences in ploidy level and chromosome constitution affect the reproductive output in these species. Although all of them show high degree of inbreeding depression (revealed by total absence of healthy seeds on forced selfing), seed and fruit set on open pollination also is extremely low. Of the three, Poonch population sets the highest percentage of healthy seeds.

For cross-pollination trees, the optimal breeding method is hybridization. Tree heterosis is commonly present and is the main research focus in tree crossbreeding. Salt stress and interspecific hybridization may lead to DNA methylation changes. The study crossed Fraxinus mandshurica (female parent) with Fraxinus velutina (male parent) to obtain interspecific F1 hybrid progenies that could obtain the good characters of parents. The results showed that growth and survival rate of the interspecific hybrid progenies (F1 hybrids of F. mandshurica × F. velutina) were significantly higher than those of intraspecific open pollinated plants from parental F. mandshurica and F. velutina. Salt tolerance and cytosine methylation in interspecific F1 hybrids and the intraspecific open pollinated plants from parents were examined. Membrane permeability, ROS and antioxidant activity, malondialdehyde, and photosynthesis were measured after salt treatment and genomic methylation was analyzed using a methylation-sensitive amplified polymorphism protocol. F1 hybrids exhibited heterosis for growth in normal as well as high salt conditions. DNA methylation in the F1 hybrids was lower than the intraspecific open pollinated plants from parents. Salt treatments changed DNA methylation patterns in F1 hybrids. Genomic DNA of the intraspecific open pollinated plants from parents had internal cytosine methylation (average of 13.22 %), whereas F1 hybrid seedlings had external cytosine methylation (average of 7.34 %). Such changes in DNA methylation patterns in F1 hybrids suggest a connection between salt tolerance and epigenetic mechanisms in plants. We observed that alteration of DNA methylation was closely correlated with the adaptation to the salt stress and provided epigenetic mechanisms of salt tolerance in the interspecific hybridization of trees.

Ruderal species may provide pollen and nectar to maintain the pollinators of crops in periods of floral resource shortage. The knowledge about the floral biology of these plant species and their interaction with insects is important for management strategies of agricultural systems. The study was carried out at an experimental research station in two different periods (August 2010-April 2011 and August 2012-January 2013). Floral biology was studied, and the reproductive system and reproductive efficacy (RE) were analyzed using controlled pollination experiments. Furthermore, floral visitors and pollination were identified and quantified. Reproductive success obtained in the open pollination and cross-pollination experiments was higher than those obtained in spontaneous self, hand self, and wind pollination. Richardia grandiflora bloomed throughout the experimental period, and flowers were visited by Coleoptera, Diptera, Hymenoptera, and Lepidoptera, which were observed foraging for pollen and/or nectar. Among the floral visitors, bees were the richest and most frequent group and often contacted anthers and stigmas during visits. Africanized honeybees touched the floral reproductive structures in all visits, and their frequency may be related to changes in the reproductive efficacy between the study periods. Pollinator species of crops cultivated at the experimental research station were frequent bee visitors of R. grandiflora. We demonstrated that R. grandiflora requires cross-pollination and biotic pollen vectors. Among floral visitors, bees are the main pollinators, especially the Africanized honeybees. R. grandiflora can be considered an important ruderal species for maintaining bee pollinator populations at the study site, providing resources during the period that crops are not blooming.

The use of maize streak virus (MSV) resistance cultivars as donors in broadening the quality protein maize (QPM) inbreds would not only reduce the virulence of the disease but also improve grain yield and quality protein in Africa. This experiment was executed by evaluating the general (GCA) and specific combining ability (SCA) of MSV resistance and QPM inbred lines for MSV resistance disease, grain yield and quality protein. Five QPM inbreds (lines) and five open pollinated MSV resistant cultivars were introgressed in a partial diallel design excluding reciprocals. The obtained 45 F1 topcross hybrids, 10 parents, and 2 local varieties that served as checks were evaluated at the Lower Niger River Basin Authority, Oke-Oyi, Nigeria in 2014 and 2015 cropping seasons. The QPM lines derived from TZEQI 76, TZEQI 87 and TZEQI 79 that were introgressed with MSV resistant Acr. 91Suwan-1-SR C1 featured as most promising for MSV resistance, high grain yield, and grain quality protein hybrids. The ratio of k2GCA/k2SCA that was more than one for grain yield and less than one for MSV resistance, lysine and tryptophan characters, indicating that additive nature conditioning the inheritance of grain yield only. The evidence from this investigation would be worthwhile for developing MSV disease resistant, high grain yielding quality protein maize varieties in Africa.

Fitness in tall fescue could be determined as the relative seed production by overcoming self-incompatibility barriers. This study was an attempt to investigate the effects of plant genotype and symbiotic fungal endophyte on seed production and associated traits in tall fescue. Fifteen clones of tall fescue free from endophyte and two clones with both endophyte-infected (E+) and non-infected (E−) counterparts were evaluated under two pollination systems of natural open-pollination and obligate self-pollination. Although seed yield was depressed by self-pollination in all E− genotypes, some genotypes exhibited reasonable selfing ratio. However, endophyte infection was much more effective to increase selfing ratio and seed yield through self-pollination particularly in the genotype 75B. Endophyte infection almost removed self-incompatibilty in the host plants and on average resulted in 3.0 times more number of seeds per self-pollinated seedheads than the non-counterpart E− tall fescue genotypes. Although it may need more elaborated studies, incorporating Epichloe fungal endophyte in plant genotypes not only may make the inbreeding in tall fescue possible but also may improve forage yield and seed production, simultaneously.