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Einkorn (Triticum monococcum L.) can be applied as a model species for cereal genomic studies due to its small genome size and high level of polymorphism. The in vitro somatic tissue culture protocol in einkorn was significantly improved recently, however the in vitro androgenesis remained an unresolved research topic. Five different pre-treatments were compared to study the effects of stress pre-treatments on the efficiency of androgenesis in two einkorn genotypes. The long cold pre-treatment (2 weeks, 4 °C) of donor tillers increased significantly the number of microspore derived embryo-like structures (ELS). Green and albino plantlets were regenerated from these structures. The ploidy level of microspore-derived green plantlet was determined as haploid by flow cytometric analyses. This is the first report published on the successful androgenesis induction (ELS production) and green- and albino plantlet regeneration in in vitro anther culture of the recalcitrant einkorn wheat (Triticum monococcum L.).

This is the first report on isolated microspore culture—derived spelt wheat. The efficiency of anther- and isolated microspore was compared using four genotypes (‘Franckenkorn’, ‘GK Feher’, ‘Mv Martongold’, ‘Oberkulmer Rotkorn’). In anther culture, genotype dependency was observed, and cold pre-treatment enhanced the efficiency of the method. In isolated microspore culture, the ovary co-culture supported the development of embryo-like structures. The presence of growth regulators (0.5 mg/l 2,4-D and 0.5 mg/l kinetin) were not essential for the induction of androgenesis, but these increased the production of embryo-like structures, green and albino plantlets. The low plant regeneration rate and high number of albinos hinder the practical application of isolated microspore culture while anther culture was efficient for in vitro green plantlets production in spelt wheat. The mean of green plantlets production was 41.45/100 anthers (from 20.93 to 83.07 depending on genotype). The phenomenon of albinism was mitigated in anther culture (3.48 albinos/100 anthers). Altogether, 1720 anther culture—derived green plantlets were produced from the four genotypes.

Drought has significant effect on wheat production by decreasing grain yield. Phenotyping the populations is a useful tool for understanding the interactions between phenotype and genotype. 135 doubled haploid (DH) genotypes and their parental varieties Plainsman (Pl) and Cappelle Desprez (CD) were phenotyped in glasshouse under well-watered (WW) and drought-stress (DS) conditions. The response of plant height, heading time, aboveground biomass, grain yield, root dry mass harvest index (HI) under both conditions, and stress tolerance index (STI) and water consumption in WW conditions was studied. We found 20% decrease in the plant growth, 66% decrease in the aboveground biomass, and 77% decrease in the grain yield. Under WW conditions, high water consumption was not related to high yields, STI, and HI. The tolerant and the sensitive genotypes were selected. In the WW and water consumption treatment, the sensitive genotype group had better grain yield performance, but under DS, the tolerant group had higher grain yield. The average yield loss was 59% in the tolerant group compared to the WW treatment, and the sensitive yield loss was 68%. Correlation was found between the grain yield and root dry mass in the tolerant group. There was significant difference between the tolerant and sensitive groups on water consumption, as the sensitive genotypes had higher water need. We found strong positive correlation between the water consumption and the grain yield in the tolerant group. This study showed that the tolerant genotypes had improved water regulating efficiency.

Members of the aldo–keto reductase family including aldose reductases are involved in antioxidant defense by metabolizing a wide range of lipid peroxidation-derived cytotoxic compounds. Therefore, we produced transgenic wheat genotypes over-expressing the cDNA of alfalfa aldose reductase gene. These plants consequently exhibit 1.5–4.3 times higher detoxification activity for the aldehyde substrate. Permanent drought stress was generated in the greenhouse by growing wheat plants in soil with 20 % water capacity. The control and stressed plants were monitored by a semi automatic phenotyping platform providing computer-controlled watering, digital and thermal imaging. Calculation of biomass values was based on the correlation (R 2 = 0.7556) between fresh weight and green pixel-based shoot surface area. The green biomass production by plants of the three transgenic lines was 12–26–41 % higher than the non-transgenic plants’ grown under water limitation. Thermal imaging of stressed non-transgenic plants indicated an elevation in the leaf temperature. The thermal status of transformants was similar at both normal and suboptimal water regime. In drought, the transgenic plants used more water during the growing season. The described phenotyping platform provided a comprehensive data set demonstrating the improved physiological condition of the drought stressed transgenic wheat plants in the vegetative growth phase. In soil with reduced water capacity two transgenic genotypes showed higher seed weight per plant than the control non-transgenic one. Limitation of greenhouse-based phenotyping in analysis of yield potential is discussed.

Two haploid induction media (190-0 and W14mi) were tested in isolated microspore culture of two triticale (X Triticosecale Wittmack) genotypes. The W14mi medium proved superior for the production of green plantlets in both genotypes. This basic medium (W14) was used to compare two doubled haploid production methods (isolated microspore culture and anther culture) with the same genotypes. The induction of androgenesis was more effective in isolated microspore culture than in anther culture. The number of embryo-like structures was 9.2 times higher in microspore culture (511.0/100 anthers) compared to anther culture (55.5/100 anthers) and the number of regenerant plantlets was also 3.4 times higher (anther culture—20.15/100 anthers; isolated microspore culture—67.6/100 anthers). However, the regenerant plantlets from isolated microspore culture were mainly albinos while predominantly green plantlets were regenerated from anther culture. The production of green plantlets from anther culture (16.8/100 anthers) was 2.9 times higher than from isolated microspore culture (5.8/100 anthers). The efficiency of anther culture was tested with eight winter triticale genotypes. The phenomenon of albinism did not hinder the green plant production in anther culture. Mean green plantlet production was 10.87/100 anthers. This value was two times higher than the number of albinos (5.01/100 anthers) and higher than previously published reports. The anther culture protocol described in this study is an efficient tool for the production of microspore-derived green plantlets in triticale.

The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian (‘Szegedi 80’, ‘Szegedi 178’, and ‘Remeny’) and three Spanish (‘Jeromin’, ‘Jariza’, and ‘Jaranda’) pepper genotypes was investigated. Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore cultures. Co-cultures with wheat, line ‘CY-45’, ovaries exhibited enhanced frequency of embryoid production than those with pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three ‘Jariza’, three ‘Jaranda’, and a single ‘Szegedi 80’ plant.

Androgenesis of wheat, rice and triticale was studied in isolated microspore culture. It is the first publication which studies microspore culture reaction of Hungarian rice varieties. The effect of different basic media, lack and absence of growth regulators in culture media were tested on important parameters of microspore culture. Direct embryogenesis was observed in microspore culture of wheat and triticale genotypes. In the case of rice, calli were induced in isolated rice microspore culture and haploid rice plantlets were regenerated via organogenesis. In wheat, the effect of basic media (W14, A2, CHB3, P4-m) was compared and among them the W14, and A2 had a superior effect on embryo production and albino and green plantlet regeneration. In rice the C, CHB3 and MSm media were tested in microspore culture and the significantly highest numbers of calli were achieved by using C and CHB3 media depending on the genotypes. The lack of exogenous growth regulators was observed in isolated microspore culture of triticale and rice. Growth regulator-free medium had a positive effect on embryo production and plant regeneration of triticale genotypes, whereas in rice microspore culture multicellular structures did not continue their division without growth regulators from the third week of microspore culture. Developing of microspore-origin calli was maintained by supplement of 2,4-D and Kinetin combination in the microspore culture medium.