Maize is the third most important cereal crop worldwide. However, its production is vulnerable to heat stress, which is expected to become more and more severe in coming years. Germplasm resilient to heat stress has been identified, but its underlying genetic basis remains poorly understood. Genomic mapping technologies can fill the void, provided robust markers are available to tease apart the genotype-phenotype relationship. In the present investigation, we used data from an RNA-seq experiment to identify single nucleotide polymorphisms (SNPs) between two contrasting lines, LM11 and CML25, sensitive and tolerant to heat stress, respectively. The libraries for RNA-seq were made following heat stress treatment from three separate tissues/organs, comprising the top leaf, ovule, and pollen, all of which are highly vulnerable to damage by heat stress. The single nucleotide variants (SNVs) calling used STAR mapper and GATK caller pipelines in a combined approach to identify highly accurate SNPs between the two lines. A total of 554,423, 410,698, and 596,868 SNVs were discovered between LM11 and CML25 after comparing the transcript sequence reads from the leaf, pollen, and ovule libraries, respectively. Hundreds of these SNPs were then selected to develop into genome-wide Kompetitive Allele-Specific PCR (KASP) markers, which were validated to be robust with a successful SNP conversion rate of 71%. Subsequently, these KASP markers were used to effectively genotype an F2 mapping population derived from a cross of LM11 and CML25. Being highly cost-effective, these KASP markers provide a reliable molecular marker toolkit to not only facilitate the genetic dissection of the trait of heat stress tolerance but also to accelerate the breeding of heat-resilient maize by marker-assisted selection (MAS).

Abstract:In the present study, thirty accessions of tomato were evaluated for estimation of correlation and path analysis among various quantitative and qualitative characters related to fruit yield. There were highly significant differences among the accessions for all the characters studied as per the analysis of variance. Genotypic correlation coefficients were generally similar in nature and higher in magnitude than the corresponding phenotypic correlation coefficients. The results revealed that the fruit yield plant -1 was significantly and positively correlated with number of fruits plant -1 (0.3119 and 0.3184) followed by fruit set percentage (0.2434 and 0.2499), fruit weight (0.6766 and 0.6731), polar diameter of fruit (0.4687 and 0.4635) at genotypic and phenotypic level, respectively, indicating that effective improvement in fruit yield plant -1 through these characters could be achieved. Fruit weight showed positive and significant genotypic and phenotypic correlation with fruit yield plant -1 by having greatest positive direct effect (1.1298 and 1.1116) on fruit yield plant -1 at both levels, indicating the true relationship between them and the feasibility to exploit the potentiality of this trait for effective direct selection to improve fruit yield plant -1 .

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1,2:5,6‐Di‐O‐cyclohexylidene‐D‐mannitol is one of the protected forms of D‐mannitol. Both terminal 1,2‐diol functions are protected with a cyclohexylidene group, and the central diol functionality is available for chemical transformations and is generally subjected to oxidative cleavage. This chapter describes the procedure for preparation of 1,2:5,6‐Di‐O‐cyclohexylidene‐D‐mannitol and 2,3‐cyclohexylidene‐D‐glyceraldehyde. It presents some of the important points to be considered, the conditions that need to be maintained, characterization data, and the reagents required, as well as the techniques used and the equipment setup that are vital to carrying out the process. The chapter also describes the hazards associated with working with chemicals and the ways to deal with these hazards.

The present study was aimed to investigate the yield and its contributing traits among indeterminate tomato genotypes in order to generate information regarding the extent of genetic variability, heritability and genetic advance. The experiment was conducted using a randomized complete block design with three replications at Vegetable Research Farm, Department of Horticulture, SHIATS, Allahabad during 2012-2013 cropping season. The analysis of variance revealed highly significant differences among all genotypes for the characters. Analysis of coefficient of variation revealed that the magnitude of phenotypic coefficient of variation was higher than genotypic coefficient of variation for all traits under study. The leaf curl incidence (39.73 and 39.74) and ascorbic acid (27.62 and 27.67) recorded high genotypic and phenotypic coefficients of variation, indicating higher magnitude of variability for these characters, thus the scope for improvement of these characters through simple selection would be better. The estimates of heritability were high for all the traits and ranged from 95 to 100 percent, suggested that selection based on phenotypic expression could be relied upon as there is major role of genetic constitution in the expression of these characters. High heritability accompanied with high genetic advance were noted for fruit yield per plant (1129.78), plant height (43.37), number of flowers per plant (40.35), number of leaves per plant (25.48) and ascorbic acid (21.68) indicating that these characters are under additive gene effects and that these traits could be considered as reliable indices for selection and higher responses of this trait could be expected from selection.

Heat stress (HS) is one of the alarming issues today due to global warming and is the foremost detrimental to crop production. Maize is one of the versatile crops grown over different agro-climatic conditions. However, it is significantly sensitive to heat stress, especially during the reproductive phase. The heat stress tolerance mechanism is yet to be elucidated at the reproductive stage. Thus, the present study focused on identifying transcriptional changes in two inbreds, LM 11 (sensitive to HS) and CML 25 (tolerant to HS), under intense heat stress at 42°C during the reproductive stage from three tissues viz. flag leaf, tassel, and ovule. Samples from each inbred were collected after 5 days of pollinations for RNA isolation. Six cDNA libraries were constructed from three separate tissues of LM 11 and CML 25 and sequenced using an Illumina HiSeq2500 platform. A total of 2,164 (1127 up-regulated and 1037 down-regulated) differentially expressed genes (DEGs) were identified with 1151, 451, and 562 DEGs in comparisons of LM 11 and CML 25, corresponding to a leaf, pollen, and ovule, respectively. Functional annotated DEGs associated with transcription factors (TFs) viz. AP2, MYB, WRKY, PsbP, bZIP, and NAM, heat shock proteins (HSP20, HSP70, and HSP101/ClpB), as well as genes related to photosynthesis (PsaD & PsaN), antioxidation (APX and CAT) and polyamines (Spd and Spm). KEGG pathways analyses showed that the metabolic overview pathway and secondary metabolites biosynthesis pathway, with the involvement of 264 and 146 genes, respectively, were highly enriched in response to heat stress. Notably, the expression changes of the most common HS-responsive genes were typically much more significant in CML 25, which might explain why CML 25 is more heat tolerant. Seven DEGs were common in leaf, pollen, and ovule; and involved in the polyamines biosynthesis pathway. Their exact role in maize heat stress response would warrant further studies. These results enhanced our understanding to heat stress responses in maize.

Introduction: Cerebrovascular disease in childhood is relatively rare. Recently, there has been much interest in homocysteine, a sulfur-containing amino acid, as an important risk factor for vascular diseases including stroke. We report the case of a 13-year-old girl presented with ischemic stroke due to hyperhomocysteinemia. Case report: This case report describes a 13-year-old girl with repeated episodes of hemiplegia due to hyperhomocysteinemia. Conclusion: There are strong clues in favor of a causal relationship between hyperhomocysteinemia and athero-trombotic diseases. Homocysteine levels can be lowered effectively by a combination therapy of folic acid, vitamin B12, and vitamin B6.

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