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Understanding the relationships between leaf photosynthetic activity and physiological and morphological traits of soybeans [Glycine max. (L.) Merr.] with different stem growth habits could be exploited for yield improvement. Leaf photosynthetic rate (Pn), stomatal conductance (gs), leaf mass per unit area (LMA), and leaf nitrogen content per unit area (LNC) were measured for field-grown progeny of a cross between an indeterminate type, 'Stressland', and a determinate type, 'Tachinagaha', soybean. The Pn, of the uppermost fully expanded leaves of Stressland was 19% greater than Tachinagaha during the first 20 d after seed filling (growth stage R5) in 2005. Among 18 F3 lines, Pn at 14 d after R5 in 2005 varied from 22.1 to 34.2 µmol CO2 m-2 s-1 and was more strongly and significantly correlated with gs (P < 0.01) than with LMA (P < 0.05) and LNC (P = 0.11). In 2006, Pn of eight selected F4 genotypes and the parents varied from 27.9 to 35.0 µmol CO2 m-2 s-1. Leaf gas exchange activity of the selected lines was represented by two attributes; the maximum of gs (gmax), and functional leaf lifespan (LL). Values of gmax were positively correlated with stomatal density (r = 0.91, P < 0.01), and LL was positively correlated with LMA (r = 0.89, P < 0.01). Some indeterminate types had very high gmax but exhibited shorter LL. Genetic improvement of maximum leaf photosynthesis appears possible by increasing stomatal density, and the Dt1 locus for stem habit has a positive effect on soybean leaf photosynthesis, both in its maximum and duration. [ABSTRACT FROM AUTHOR]

Isozyme banding patterns (IBPs) were studied for cultivars of lily (Liliumspp.) by means of horizontal starch–gel electrophoresis (SGE). An array of continuous histidine–citrate buffer systems at eight ranges of pH and four extraction buffers were tested. On the basis of this survey, the extraction buffer two (Eb-2) and the buffer system E at pH 7.7 were found to be suitable for detection of lily isozymes. Using the SGE technique, IBP in catalase (CAT; EC 1.11.1.6), esterase (EST; EC 3.1.1.1), malate dehydrogenase (MDH; EC 1.1.1.37), malic enzyme (MAL; EC 1.1.1.40), peroxidase (POX; EC 1.11.1.7), phosphoglucomutase (PGM; EC 2.7.5.1), phosphoglucose isomerase (PGI; EC 5.3.1.9) and 6-phosphogluconate dehydrogenase (PGD; EC 1.1.1.44) were assayed. In total 29 cultivars were tested in this study: nine were analysed for all eight enzyme systems, 16 cultivars for seven systems, three for six, and one for five enzyme systems. Some IBP were identified as section-specific biochemical markers. Eight enzymes systems were analysed by constructing a dendogram using the unweighted pair group method, arithmetic average (UPGMA) cluster analysis. The analysis indicated that the lily cultivars could be separated from otherLiliumspecies, except for twoL. x formonlogicultivars:‘Hakuba’ and‘Hakuko’ which could not be distinguished from each other by the isozyme patterns assayed here. This study shows that isozymes can provide useful biochemical markers for lily cultivar identification and to estimate the phylogenetic relationships among those cultivars. [ABSTRACT FROM AUTHOR]

Abstract A PCR-based technique for detection of clavicipitaceous pathogens in rice and related grasses was developed. The target pathogens were Ustilaginoidea virens , which causes rice false smut, and Ephelis japonica , which causes rice udbatta disease and black choke in grasses. To design specific primers, a comparison was made on genetic diversity on the rDNA internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene of U. virens, Ephelis japonica , as well as some other clavicipitaceous fungi. Each fungus was successfully detected by using a specific primer set with high sensitivity. Species-specific primers designed here were capable of detecting these pathogens in plant tissues. The PCR detection was consistent with conventional histological observation. This nested PCR assay was sensitive and reliable for the detection of U. virens and E. japonica , and thus can be a used to study disease cycles and early prediction of false smut and udbatta-disease incidence in fields. [ABSTRACT FROM AUTHOR]

Presents a study conducted on screening of genetic loci for seed dormancy in rice. Detailed information on the methodology used to conduct the study; Discussion based on the results of the study.

Successful hybridization between Lilium concolor and Lilium longiforum has not been reported but ovary slice culture technique, after cut-style pollination has now been used to produce diploid and triploid interspecific hybrids between these species. Reciprocal crosses between diploid cultivars (2n = 2x = 24) were conducted. 5, 10, 15, 20, 25, 30, 35, 40, and 45 days after pollination (DAP), ovaries were sliced and cultured on a modified Murashige and Skoog (MS) medium without growth regulators and NH[sub4]NO[sub3], supplemented with 6% sucrose, 50mg/I yeast extract and 0.25% gelrite at pH 6.3. For the L. concolor x L. longiflorum cross, embryo germination was found to be best at 20 DAP, while for the L. longiflorum x L concolor at 25 DAP. After transfer to a MS (half-strength) medium supplemented with 1.5% sucrose, 0.25% gelrite and 0.2% active charcoal at pH 5.8, diploid and triploid hybrid plants were developed. All regenerated plants were identified as hybrids on the basis of karyotype and isozyme analyses. Ovary slice culture technique as a method of producing polyploids is discussed. [ABSTRACT FROM AUTHOR]

Ovary slice culture, after cut-style pollination, was used to develop interspecific hybrids between Lilium longiflorum and L. concolor. Reciprocal crosses between diploid cultivars (2n = 2x = 24) were carried out. On the days 30, 35, 40 and 45th after pollination (DAP), ovaries were sliced and cultured on a modified hormone-free Murashige-Skoog (M-S) medium without NH4NO3, supplemented with 6% sucrose, 50 mg/l yeast extract and 0.25% gelrite at pH 6.3. For the L. longiflorum × L. concolor cross, ovule germination was found to be best at 30 DAP. After transfer to a M-S (half-strength) medium supplemented with 1.5% sucrose and 0.25% gelrite at pH 5.8, diploid and triploid hybrid plants were established. In contrast, ovules from the L. concolor × L. longiflorum cross did not germinate. The hybridity of the plantlets obtained was verified by karyotype and isozyme analysis. The importance of the ovary slice culture technique as a tool to develop new hybrids between incompatible lilly plants is discussed. [ABSTRACT FROM AUTHOR]