Background Salinity expansion in arable land is a threat to crop plants. Rice is the staple food crop across several countries worldwide; however, its salt sensitive nature severely affects its growth under excessive salinity. FL478 is a salt tolerant indica recombinant inbred line, which can be a good source of salt tolerance at the seedling stage in rice. To learn about the genetic basis of its tolerance to salinity, we compared transcriptome profiles of FL478 and its sensitive parent (IR29) using RNA-seq technique. Results A total of 1714 and 2670 genes were found differentially expressed (DEGs) under salt stress compared to normal conditions in FL478 and IR29, respectively. Gene ontology analysis revealed the enrichment of transcripts involved in salinity response, regulation of gene expression, and transport in both genotypes. Comparative transcriptome analysis revealed that 1063 DEGs were co-expressed, while 338/252 and 572/908 DEGs were exclusively up/down-regulated in FL478 and IR29, respectively. Further, some biological processes (e.g. iron ion transport, response to abiotic stimulus, and oxidative stress) and molecular function terms (e.g. zinc ion binding and cation transmembrane transporter activity) were specifically enriched in FL478 up-regulated transcripts. Based on the metabolic pathways analysis, genes encoding transport and major intrinsic proteins transporter superfamily comprising aquaporin subfamilies and genes involved in MAPK signaling and signaling receptor kinases were specifically enriched in FL478. A total of 1135 and 1894 alternative splicing events were identified in transcripts of FL478 and IR29, respectively. Transcripts encoding two potassium transporters and two major facilitator family transporters were specifically up-regulated in FL478 under salt stress but not in the salt sensitive genotype. Remarkably, 11 DEGs were conversely regulated in the studied genotypes; for example, OsZIFL , OsNAAT , OsGDSL, and OsELIP genes were up-regulated in FL478, while they were down-regulated in IR29. Conclusions The achieved results suggest that FL478 employs more efficient mechanisms (especially in signal transduction of salt stress, influx and transport of k + , ionic and osmotic homeostasis, as well as ROS inhibition) to respond to the salt stress compared to its susceptible parent. Electronic supplementary material The online version of this article (10.1186/s12284-019-0273-2) contains supplementary material, which is available to authorized users.

Study of combining ability and heterosis were conducted on 12 F1 hybrids along with seven rice genotypes (three
cytoplasmic male sterile lines and four restorer varieties) to know the pattern of inheritance of some
morphological traits for selecting superior genotypes. The experiment was carried out according to line x tester
mating design, during 2007-08. Analysis of variance revealed significant differences among genotypes, crosses,
lines, testers and line x tester interactions for tiller number, plant height, days to 50% flowering, panicle length,
number of spikelets per panicle, spikelet fertility and grain yield traits. Variances of SCA were higher than the
GCA variances for traits except for plant height which indicated predominance of non-additive gene action in the
inheritance of the traits. The highest heterosis (106.60%) was observed in cross IR68899A x Poya followed by
other eight crosses for yield and most of its related traits. The proportional contribution of testers was observed
to be higher than that of the interactions of line x tester that revealed the higher estimates of GCA variance that is
additive gene action among the testers used. Within CMS parents, IR62829A and among male parents, IR50 and
Poya were observed to be good general combiners for most of the characters studied. The cross combinations
IR62829A x Mosa-tarom, IR68899A x Poya, IR58025A x IR50 and IR58025A x Poya were observed to be good
specific cross combinations for grain yield and most of its related traits due to highly significant SCA and
heterotic effects

The chamazulene and α-(−)-bisabolol contents and quality of the chamomile oil are affected by genetic background and environmental conditions. Salicylic acid (SA), as a signaling molecule, plays a significant role in the plant physiological processes. The aim of this study was to evaluate the chemical profile, quantity, and improve the essential oil quality as a consequence of the increase of chamazulene and α-(−)-bisabol using salicylic acid under normal and heat stress conditions by the gas chromatography-mass spectrometry (GC-MS) technique. The factorial experiments were carried out during the 2011–2012 hot season using a randomized complete block design with three replications. The factors include four salicylic acid concentrations (0 (control), 10, 25 and 100 mg·L−1), and three chamomile cultivars (Bushehr, Bona, Bodegold) were sown on two different planting dates under field conditions. Fourteen compounds were identified from the extracted oil of the samples treated with salicylic acid under normal and heat stress conditions. The major identified oil compositions from chamomile cultivars treated with salicylic acid were chamazulene, α-(−)-bisabolol, bisabolone oxide, β-farnesene, en-yn-dicycloether, and bisabolol oxide A and B. Analysis of variance showed that the simple effects (environmental conditions, cultivar and salicylic acid) and their interaction were significant on all identified compounds, but the environmental conditions had no significant effect on bisabolol oxide A. The greatest amount of chamazulene obtained was 6.66% at the concentration of 10 mg·L−1 SA for the Bona cultivar under heat stress conditions, whereas the highest α-(−)-bisabolol amount attained was 3.41% at the concentration of 100 mg·L−1 SA for the Bona cultivar under normal conditions. The results demonstrated that the application of exogenous salicylic acid increases the quantity and essential oil quality as a consequence of the increase of chamazulene and α-(−)-bisabolol under normal and heat stress conditions.

The Bacillus pumilus SG2 chitinase gene (ChiS) and its truncated form lacking chitin binding (ChBD) and fibronectin type III (FnIII) domains were transformed to Arabidopsis plants and the expression, functionality and antifungal activity of the recombinant proteins were investigated. Results showed that while the two enzyme forms showed almost equal hydrolytic activity toward colloidal chitin, they exhibited a significant difference in antifungal activity. Recombinant ChiS in plant protein extracts displayed a high inhibitory effect on spore germination and radial growth of hyphae in Alternaria brassicicola, Fusarium graminearum and Botrytis cinerea, while the activity of the truncated enzyme was strongly abolished. These findings demonstrate that ChBD and FnIII domains are not necessary for hydrolysis of colloidal chitin but play an important role in hydrolysis of chitin-glucan complex of fungal cell walls. Twenty microgram aliquots of protein extracts from ChiS transgenic lines displayed strong antifungal activity causing up to 80% decrease in fungal spore germination. This is the first report of a Bacillus pumilus chitinase expressed in plant system.

Abstract:The objective of this study was to investigate the effect of exogenous application of salicylic acid concentrations on the physiological and biochemical traits and essential oil content of chamomile under normal and heat stress conditions as induced by delayed sowing. The experiments were conducted during 2011-2012 as a factorial using a randomized complete block design with three replications, in a very hot region. The factors included five salicylic acid concentrations (0 (control), 1, 10, 25 and 100 mg¨L´1) and three chamomile cultivars (Bushehr, Bona, Bodegold). The seeds of chamomile were sown on two different sowing dates including an optimum planting date and a late planting date. The physiological traits (plant height, capitol diameter, 1000 grain weight, fresh and dried flower weight), total chlorophyll, proline and essential oil content were investigated. Analysis of variance showed that the effect of the environmental conditions (normal and heat stress) was significant on all physiological and biochemical traits with the exception of the essential oil content. The heat stress decreased physiological traits and total chlorophyll in comparison with the normal conditions but it had no significant effect on the essential oil content. Findings indicated that the application of exogenous salicylic acid improves essential oil content in chamomile cultivars under environmental heat stress conditions.