The role of relative humidity (RH) while processing and storing seeds of Brassica spp. and Eruca sativa was investigated by creating different levels of relative humidity, namely, 75%, 50%, 32%, and 11% using different saturated salt solutions and 1% RH using concentrated sulphuric acid. The variability in seed storage behaviour of different species of Brassica was also evaluated. The samples were stored at 40 ± 2°C in sealed containers and various physiological parameters were assessed at different intervals up to three months. The seed viability and seedling vigour parameters were considerably reduced in all accessions at high relative humidity irrespective of the species. Storage at intermediate relative humidities caused minimal decline in viability. All the accessions performed better at relative humidity level of 32% maintaining seed moisture content of 3%. On analyzing the variability in storage behaviour, B. rapa and B. juncea were better performers than B. napus and Eruca sativa.

Root-knot nematodes (RKNs) are devastating parasites that infect thousands of plants. As RKN infection is facilitated by oesophageal gland effector genes, one such effector gene, Mi-msp2, was selected for a detailed characterization. Based on domain analysis, the Mi-MSP2 protein contains an ShKT domain, which is likely involved in blocking K+ channels and may help in evading the plant defence response. Expression of the Mi-msp2 gene was higher in juveniles (parasitic stage of RKNs) than in eggs and adults. Stable homozygous transgenic Arabidopsis lines expressing Mi-msp2 dsRNA were generated, and the numbers of galls, females and egg masses were reduced by 52–54%, 60–66% and 84–95%, respectively, in two independent RNAi lines compared with control plants. Furthermore, expression analysis revealed a significant reduction in Mi-msp2 mRNA abundance (up to 88%) in female nematodes feeding on transgenic plants expressing dsRNA, and northern blot analysis confirmed expression of the Mi-msp2 siRNA in the transgenic plants. Interestingly, a significant reduction in the reproduction factor was observed (nearly 40-fold). These data suggest that the Mi-msp2 gene can be used as a potential target for RKN management in crops of economic importance.

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The 44 accessions which were collected from Rajasthan, Gujarat and M.P. were evaluated in a randomized complete block design with three replicates during <italic>summer</italic> and <italic>kharif</italic> seasons in the hot arid climate of western Rajasthan to estimate the presence of genetic variability, inter-characters associations, to identify a suitable accession for cultivation during <italic>summer</italic> and to compare the relative performance of the genotypes in two seasons. The high degree of genetic variability was estimated during both seasons for seed yield per plant (g), plant height (cm.), pod length (cm.), peduncle length (cm.), number of branches per plant (cm), number of clusters per plant, number of cluster per branch and cluster length (cm.). The moderate to high heritabilities coupled with moderate expected genetic advance were observed for all studied traits. The plant height, pod length, number of branches per plant exhibited positive and significant association with seed yield whereas the incidence of leaf crinkle virus and yellow mosaic virus correlated negatively and significantly with seed yield. The accession IC 39786 exhibited absolute genetic resistance to crinkle virus disease in the field conditions. The accessions IC 36245, IC-36555, IC 36667, IC 36577 and IC 36604 exhibited yield advantage over best check during <italic>summer</italic> whereas accessions IC- 39675, IC-36607, IC-251908, IC 36245 and IC-36563 performed better than best check in terms of seed yield during <italic>kharif</italic> season.

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