Fifteen million farmers in India engaged in Maize cultivation. India would require 45 MMT of Maize by 2022. But, only 15% of cultivated area of maize is under irrigation and water shortage has been a challenge for sustainability of maize production. Water deficit stress (WDS) during pre-flowering and grain filling stages massively affects the plant performance due to imprecise traits function. Thus, the effect of WDS on non-drought tolerant (NDT) and drought tolerant (DT) maize lines were investigated. WDS increased the flowering days, days to maturity, anthesis silk interval, decreased the leaf number, abnormal expression of secondary stress responsive traits, loss of normal root architecture which overall lead to a reduction in GY/ha. WDS at flowering and grain filling stage leads to significant yield penalty especially in NDT lines than DT lines. The yield penalty was ranged from 34.28 to 66.15% in NDT and 38.48 to 55.95% in DT lines due to WDS. Using multiple statistics, traits which improve WDS tolerance in maize were identified viz; number of leaves, number of stomata on lower surface of leaf, leaf angle at ear forming node internodal length between 3 rd and 4 th leaf from top, flag leaf length, flag leaf width, ear per plants, leaf senescence, pollen stainability, root fresh weight and root length. These traits would help in trait specific breeding in maize for WDS tolerance.

Eleven pigmented rice genotypes were evaluated to estimate genetic parameters, heritability and association. The results indicated that, genotypic variation was high among the lines. The distinct seasonal effect on plant performance for antioxidant capacity, anthocyanin, flavonoids, head rice recovery and test weights was also observed. Wet season favoured the crop performance in all genotypes as compared to drought conditions. The differential accumulation of different quality traits such as AOA, anthocyanin content, flavonoids content, etc showed high heritability, which would be transfer to high yeilding popular rice cultivars through conventional or geneticaly modification techniques. The line Mamihunger was chosen as donor of the high-quality rice grain and Annapurna for high yield. Further, Mamihunger are foreseen to be good in nutritional quality and industry use.

BACKGROUND: Phytic acid (PA) is an anti-nutrient present in cereals and pulses.It is known to reduce mineral bioavailability and inhibit starch-digesting -amylase (which requires calcium for activity) in the human gut. In principle, the greater the amount of PA, the lower is the rate of starch hydrolysis. It is reflected in the lower glycemic index (GI) value of food. People leading sedentary lifestyles and consuming rice as a staple food are likely to develop type 2 diabetes. Hence, this study was planned to understand how PA content of different rice varieties affects the GI. RESULTS: Rice Khira and Mugai which had very low PA (0.30 and 0.36 g kg −1 , respectively) had higher GI values and -amylase activity, while Nua Dhusara and the pigmented rice Manipuri black rice (MBR) which had high PA (2.13 and 2.98 g kg −1 , respectively) showed low -amylase activity and GI values. This relationship was statistically significant, though a weak relationship was found for the pigmented rice. Expression levels of MIPSI, IPKI and GBSSI markedly increased in the middle stage of grain development in all of the six genotypes having contrasting PA and GI. Maximum expression of MIPSI and IPKI was observed in Nua Dhusara and MBR (which had high PA) while that of GBSSI was observed in Khira and Mugai (with higher GI) at middle stage showing a negative correlation between PA and GI. CONCLUSIONS:The data indicate that high PA content in rice might have an adverse effect on starch digestibility resulting in slower starch digestion in the human gut and consequently low glycemic response.

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Background Early seedling vigor is an essential trait of direct-seeded rice. It helps the seedlings to compete with weeds for water and nutrient availability, and contributes to better seedling establishment during the initial phase of crop growth. Seedling vigor is a complex trait, and phenotyping by a destructive method limits the improvement of this trait through traditional breeding. Hence, a non-invasive, rapid, and precise image-based phenotyping technique is developed to increase the possibility to improve early seedling vigor through breeding in rice and other field crops. Results To establish and assess the methodology using free-source software, early seedling vigor was estimated from images captured with a digital SLR camera in a non-destructive way. Here, the legitimacy and strength of the method have been proved through screening seven diverse rice cultivars varying for early seedling vigor. In the regression analysis, whole-plant area (WPA) estimated by destructive-flatbed scanner (WPAs) and non-destructive imaging (WPAi) approaches was strongly related (R2 > 83%) and suggested that WPAi can be adapted in place of destructive methods to estimate seedling vigor. In addition, this study has identified a set of new geometric traits (convex hull and top view area) for screening breeding lines for early seedling vigor in rice, which decreased the time by 80% and halved the cost of labor in data observation. Conclusions The method demonstrated here is affordable and easy to establish as a phenotypic platform. It is suitable for most glasshouses/net houses for characterizing genotypes to understand the plasticity of shoots under a given environment at the seedling stage. The methodology explained in this experiment has been proven to be practical and suggested as a technique for researchers involved in direct-seeded rice. Consequently, it will help in the simultaneous screening of genotypes in large numbers, the identification of donors, and in gaining information on the genetic basis of the trait to design a breeding program for direct-seeded rice.

Background Asian cultivars were predominantly represented in global rice panel selected for sequencing and to identify novel alleles for drought tolerance. Diverse genetic resources adapted to Indian subcontinent were not represented much in spite harboring useful alleles that could improve agronomic traits, stress resilience and productivity. These rice accessions are valuable genetic resource in developing rice varieties suited to different rice ecosystem that experiences varying drought stress level, and at different crop stages. A core collection of rice germplasm adapted to Southwestern Indian peninsular genotyped using SSR markers and characterized by contrasting water regimes to associate genomic regions for physiological, root traits and yield related traits. Genotyping-By-Sequencing of selected accessions within the diverse panel revealed haplotype variation in genic content within genomic regions mapped for physiological, morphological and root traits. Results Diverse rice panel (99 accessions) were evaluated in field and measurements on plant physiological, root traits and yield related traits were made over five different seasons experiencing varying drought stress intensity at different crop stages. Traits like chlorophyll stability index, leaf rolling, days to 50% flowering, chlorophyll content, root volume and root biomass were identified as best predictors of grain yield under stress. Association mapping revealed genetic variation among accessions and revealed 14 genomic targets associated with different physiological, root and plant production traits. Certain accessions were found to have beneficial allele to improve traits, plant height, root length and spikelet fertility, that contribute to the grain yield under stress. Genomic characterization of eleven accessions revealed haplotype variation within key genomic targets on chromosomes 1, 4, 6 and 11 for potential use as molecular markers to combine drought avoidance and tolerance traits. Genes mined within the genomic QTL intervals identified were prioritized based on tissue specific expression level in publicly available rice transcriptome data. Conclusion The genetic and genomic resources identified will enable combining traits with agronomic value to optimize yield under stress and hasten trait introgression into elite cultivars. Alleles associated with plant height, specific leaf area, root length from PTB8 and spikelet fertility and grain weight from PTB26 can be harnessed in future rice breeding program.

Phosphorus (P) flow in agricultural land depends on the P taken off from harvested product, its losses through runoff and fertilizer applied to balance the removed P. Phytic acid (PA), the major storage form of phosphorus (P) in cereal grains is a key anti‐nutrient for human and non‐ruminants leads to eutrophication of waterways. As the natural non‐renewable P reserves are limited, enhancing P use efficiency is needed for field crops. SULTR‐like phosphorus distribution transporter (SPDT) is a novel rice transporter transfer P to the grain. Any alteration in transporter gene reduce grain P with concomitant rise in the leaves. A low PA (3.0 g/kg) rice Khira was identified where a single nucleotide mutation in LOC_Os06g05160 gene encoding SPDT showed low P transportation to grain. An amino acid change was detected as Valine‐330 to Alanine at the 3′ end of fifth exon. Highest expression of SPDT was observed in node I of rice as compared to low PA genotype. The mutation in SPDT could significantly affect P and PA accumulation in the grains with increased mineral bioavailability. Practical applications Excessive P application in crop leads to higher production cost as well as rapid depletion of limited rock phosphate. Alteration of P transporter function in the rice lower PA and total P accumulation in the grains with increased mineral bioavailability. The re‐distributed P in the straw can be applied as manure to the rice field. Thus, less P will be removed from the field, result in the decreased requirement for P fertilizer.

Rice grain yield is drastically reduced under low light especially in kharif (wet) season due to cloudy weather during most part of crop growth. Therefore, 50-60% of yield penalty was observed. To overcome this problem, identification of low light tolerant rice genotypes with a high buffering capacity trait such as photosynthetic rate has to be developed. Sedoheptulose-1,7 bisphosphatase, a light-regulated enzyme, plays pivotal role in the Calvin cycle by regenerating the substrate (RuBP) for RuBisCo and therefore, indirectly regulates the influx of CO 2 for this crucial process. We found a potential role of SBPase expression and activity in low light tolerant and susceptible rice genotypes by analyzing