Plant Genetic Resources最新文献

Efficient conservation and sustainable use of crop diversity is critical to support global food and nutritional security with ex situ collections stored in over 800 genebanks in 115 countries. The challenge is to manage those collections for long-term conservation of crop diversity and sustainable use to respond to global challenges of food security and climate change. The Genebank Standards for Plant Genetic Resources for Food and Agricutlure (Genebank Standards) form the overall framework for curation of ex situ crop collections, allowing considerable flexibility to develop customized approaches to conserving different crops. Stratified curation involves strategically tailoring curation to specific genebank goals, crops, priorities and resources for each accession based on all available information to prioritize accessions for long-term conservation. It implies using scarce resources where they are most needed and recognizes that accessions can be (a) fully curated to international standards; (b) partially curated for storage for a limited time; (c) archived and stored but no longer curated and available from the genebank; or (d) historical and removed entirely from the genebank. The stratified approach is consistent with the Genebank Standards and the policy framework of the International Treaty on Plant Genetic Resources for Food and Agriculture. Stratified curation encourages curators to make difficult decisions on accession management to better respond to challenges of curating large collections of crop diversity.

Peanut (Arachis hypogaea L.) is an important row crop rich in oil, protein, vitamins and other micro-nutrients. The intensive selection of the cultigen, a cultivated plant deliberately altered by humans through cultivation, has resulted in favourable changes in yield and biochemical composition. Nevertheless, it has generated a narrow genetic basis that limits the development of new varieties with resistance to pests, diseases and environmental stresses. In this study, we address this limitation by characterizing the proximate and fatty acid composition of a multi-disease-resistant interspecific recombinant inbred line (RIL) population derived from three wild Arachis species and a cultivated elite peanut line that is being used to widen the genetic basis of the crop. The population was also genotyped with the Axiom Arachis 48K SNP array and used to detect quantitative trait loci (QTL) for oil, protein content and oleic and linoleic fatty acid percentages. A wide range of proximate composition was found in the RIL population. Eighteen and 11 individuals had high oil and protein content, respectively, and no undesirable traits related to oil quality had been introduced into the population from wild species. The fatty acid composition of oleic and linoleic acids was found to be regulated by two major QTL. The discovery of markers within the major effect QTL for the most significant chemical traits provides new opportunities for the creation of resistant and extremely nutrient-dense peanut cultivars.

Quality protein maize (QPM) has protein quality of opaque 2 (>0.074% tryptopan) with endosperm modifiers which turn its kernels vitreous that is similar to normal maize. Use of QPM as a cereal can significantly improve daily intake of lysine and tryptophan for humans and livestock. However QPM cultivars have lower yields due to trait compensation. Therefore, a breeding programme was carried out to convert parental lines of Shalimar maize hybrid 5 (SMH-5) viz. IML-187 and BML-6 into QPM versions. Marker polymorphism was worked out in donors and recipients. IML-187 was crossed with DQL-2029-1 and BML-6 was crossed with DQL-779-2-9. The first and second backcross generations involving IML-187 as recurrent parent were marked as BC1F1 (A) and BC2F1 (A) respectively, whereas those involving BML-6 were designated as BC1F1 (B) and BC2F1 (B) respectively. The BC2F2 lines derived from two generation of backcrossing coupled with SSR marker and phenotypic background and foreground selection were advanced to BC2F3. Approximately 80–90% of RPG similarity was observed in BC2F2 lines. Eight lines namely IML-187 × DQL-2029-1- BC2F3:06, 07 and 23: BML-6 × DQl-779-2-9: 02,04,09,20 and 13 were identified from BC2F3 to have tryptophan higher than 0.075% and <25% opaqueness. These lines were used for trait fixing and crosses were made to produce QPM version of SMH-5. Six improved versions of SMH-5 were selected for higher grain yield and tryptophan content and are to be employed in further testing and varietal release in Northern Hill Zone (NHZ) in India.

Water deficit is one of the most important abiotic stresses constraining crop production in rapeseed. Understanding the mechanisms of adaptation to this stress is essential for the development and production of drought-tolerant genotypes. For this reason, this research study aims to investigate the importance of genetic diversity in identifying genotypes with a high degree of drought tolerance through assessing effectiveness of inter simple sequence repeat (ISSR) markers on 14 genotypes of rapeseed in a factorial design. Morphological and physiological characteristics were studied after the early stages of growth; in order to evaluate the genetic diversity among genotypes, 18 different ISSR markers were used. A total of 106 clear and scalable loci were amplified, of which 60 bands (56.6%) were polymorphic. The highest polymorphism information content belonged to marker number 9 with the amount of 0.365 (85.7%). Gene variation ranged from 0.081 to 0.365 and the rapeseed genotypes were divided into three groups by cluster analysis (unweighted pair group method with arithmetic mean method). The analysis of molecular variance showed that 70% of the total variation was observed within populations and 30% of this variation occurred among populations. In addition, t-test was used for comparing oil content percentage among different genotypes in control and stress levels. Adriana had the highest amount of seed oil with 36.47%, whereas Karaj 2 had the lowest amount with 27.28 and Cooper had the highest decrease in oil content percentage under stress conditions. Overall, the genotypes Likord, Hyola 401 and Sarigol 32 were identified as the most drought-tolerant.

A total of 108 diverse sorghum (Sorghum bicolor) accessions were characterized for quantitative and qualitative fodder-related traits and zonate leaf spot (ZLS) (Gloeocercospora sorghi) disease during two successive wet seasons of 2019 and 2020 in augmented randomized block design. The Shannon's diversity index and analysis of variance showed the existence of significant variability among qualitative and quantitative traits. K-mean clustering showed strong relationship between green fodder yield (GFY) and other yield-contributing traits. The dendrogram constructed based on morphological traits classified accessions into four diverse groups and most of genotype fall under cluster II. The principal component analysis bi-plot analysis showed a total variation of 68.96%, where GFY, stem weight per plant, panicle length and dry matter yield (DMY) contributed significantly. From the experimental results, three sorghum genotypes viz., IG-03-424, IG-01-436 and IG-03-438 were identified as promising for higher GFY (808.66 g/plant) and DMY (238.0 g/plant), respectively. Further, based on disease reactions under natural condition, five genotypes viz., EC-512397, EC512393, EC512394, EC512399 and IG-02-437 were identified as potential donor for resistance to ZLS disease. These selected lines could be used as promising sources for high biomass and disease resistance in forage sorghum breeding programme.

To select a stable and best-performing cluster bean line over seasons, an experiment was carried out using five shortlisted advanced breeding lines of vegetable cluster bean in randomized block design with four replications in Kharif and Summer seasons of 2019–20 and 2020–21 at ICAR-Indian Institute of Horticultural Research, Bengaluru. Additive mean effect and multiplicative interaction analysis of variation indicated a significant genotype and environment (G × E) interaction for all the traits. A high environment effect of 33.73% of the total sum of squares was observed for the trait pods per cluster followed by yield per hectare, single pod weight, pods per plant and clusters per plant. The first two interactive principal component axes (IPCA) cumulatively contributed 87.9, 97.3, 94.6, 98.6 and 85.6% variations for yield per hectare, number of clusters per plant, pods per plant, pods per cluster and single pod weight, respectively, leaving a small but significant amount of variation in the third IPCA. A mean versus weighted average of absolute score (WAAS) biplot indicated that genotype IIHRCB 26-2-1 is stable and best for the trait clusters per plant (>20 clusters/plant) while, IIHRCB 22-1-1 is superior and stable (WAAS mean nearly 0.00) for pods per cluster with >5 pods/cluster, pods per plant with >90 pods/plant, single pod weight with >3.0 g and yield per hectare around 24 t/ha. For all the environments, genotype IIHRCB 22-1-1 was found ‘all-time winner’ for yield per hectare and single pod weight. Based on multitrait stability index, IIHRCB 22-1-1 was found the best performer and the most stable genotype.

Improvement in genetic gains of crops could be achieved by phenomics' characterization of agronomic, physiological and stress-related traits. Molecular and strategic breeding programmes require broad range of foreground and background phenotypic information for crop improvement. The current experiment was performed on 123 advanced soybean (Glycine max L.) genotypes including seven local lines belongs to four different maturity groups (000-lV) to estimate the endogenous potential of various yield-related traits. The experimental trial was repeated for two cropping seasons. Four traits out of six, yield per plant (YPP), number of seeds per plant, number of pods per plant and plant height (PH), showed maximum variation (CV%) that directly correlate with variability in the subjected population. PH, number of pods, 100-seed weight and YPP showed strong positive correlation in both years. Among the principal components, factors 1 and 2 showed maximum contribution in phenotypic variability ranges from 19 to 48.5% and 26 to 47.7% in the first and second years, respectively. Number of pods showed significant positive correlation with genotypes in both years. Dendrogram showed two distinct groups of soybean genotypes. Genetic variation and association among the accessions is indispensable for effective conservation and utilization of germplasm. Principal component analysis helps to identify the diverse genotypes that will be used as a parent for various breeding programmes. These phenotypic data will be used for detection of heat stress-related quantitative trait loci with genotypic data in genome-wide association studies experiments.

Chickpea is a cool season, photothermal-sensitive crop, that is adversely affected by high temperatures (>35°C) and whose flowering is promoted by long-day conditions (>12 h). This prevents horizontal crop spread under a variety of agro-climatic conditions and the development of insensitive genotypes that perform well in all seasons. Therefore, a study was conducted to identify genotypes that are mature early, insensitive to photoperiod, high temperature and tolerant to drought stress. A set of 74 genotypes was evaluated under rainfed conditions in Kharif 2021 (off-season) to select eight promising early-maturing genotypes with high-yielding capacity. Then further investigations were conducted in five different seasons Late Kharif 2021, rabi 2021, summer 2022, early Kharif 2022 and Kharif 2022 to identify the genotypes with photothermo-insensitivity among the selected eight genotypes. With the exception of rabi 2021, each of these seasons were distinct from the chickpea's typical growing season. Among these eight, the stable genotypes which are performed better in all the seasons, especially in summer were considered, such as IPC 06-11, MNK-1, JG-14 and ICE 15654-A as a photothermo-insensitive, were able to flower and set pods with higher seed yield and, resulting in early maturity in a temperature range of 41.4/9.3°C with photoperiods of 13.1/10.9 h to reach in all seasons throughout the year. The heritability was more than 60%. Hence, these genotypes can be used as donor aids in the development of early maturing, drought stress tolerant and photothermo-insensitive chickpea.

Terminalia chebula Retz. is a multipurpose tree but the primary purpose of cultivating and raising this tree species is its fruits. Large sized fruits easily fetch higher prices in the national and global markets. The availability of superior germplasm is, however, restricted by its very low natural regeneration, poor germination capacity of the seeds, very little knowledge about its propagation techniques, long juvenile period for fruits production which is almost 15–20 years. The availability of superior germplasm and shortening of long juvenile period can be resolved by the adoption of various vegetative propagation techniques. In the present study, scions of T. chebula Retz. were grafted on three different rootstocks; T. chebula Retz., Terminalia bellirica Roxb. and Terminalia arjuna Bedd to standardize vegetative propagation techniques in T. chebula. The grafting and budding methods used were cleft grafting, side-veneer grafting and patch budding. The results revealed that out of all the propagation techniques evaluated under nursery conditions, cleft grafting was most promising. It showed better results on principal parameters like graft survival ratio (46.67) and graft take ratio (60.00). In case of rootstocks, T. arjuna performed well on most of the growth parameters. Hence, it is concluded that T. arjuna as a rootstock can be cleft grafted with T. chebula Retz. scion not only to obtain healthy plants with desired characteristics in a short time but also to conserve its germplasm.