RESUMO
Sesuvium portulacastrum (L.) is a fast-growing herbaceous perennial and halophyte belonging to the family Aizoaceae. Bioactive compound identification from halophytes is more helpful for the drug development process. The present investigation was to fractionate and identify the bioactive compounds of leaf extracts from Sesuvium potrucastrulam and evaluate their antioxidant potential. The Soxhlet extraction method was used in this study, and column chromatography was done for the partial purification. The bactericidal activity of the fraction was determined using the agar-well diffusion technique, and the effective fraction was analysed by GC-MS. A hydrogen peroxide-reducing assay was carried out on the antioxidant activity of the elite fraction. Five active fractions were collected from the crude extract. Fraction (F3) exhibited promising antibacterial and antioxidant activity. GS-MS analysis suggested the active compounds of the elite fraction are n-Hexadecanoic acid (29.70%), oleic acid (8.08%), octadecatrienoic acid (8.01%), 2-methoxy-4-vinylphenol (6.65%), tertracosamethyl-cyclododecasiloxane (6.55%), and lineolic acid (4.68%).
RESUMO
Chickpeas are often grown under receding soil moisture and suffer ~50% yield losses due to drought stress. The timing of soil water use is considered critical for the efficient use of water under drought and to reduce yield losses. Therefore the root growth and the soil water uptake of 12 chickpea genotypes known for contrasts in drought and rooting response were monitored throughout the growth period both under drought and optimal irrigation. Root distribution reduced in the surface and increased in the deep soil layers below 30cm in response to drought. Soil water uptake was the maximum at 45-60cm soil depth under drought whereas it was the maximum at shallower (15-30 and 30-45cm) soil depths when irrigated. The total water uptake under drought was 1-fold less than optimal irrigation. The amount of water left unused remained the same across watering regimes. All the drought sensitive chickpea genotypes were inferior in root distribution and soil water uptake but the timing of water uptake varied among drought tolerant genotypes. Superiority in water uptake in most stages and the total water use determined the best adaptation. The water use at 15-30cm soil depth ensured greater uptake from lower depths and the soil water use from 90-120cm soil was critical for best drought adaptation. Root length density and the soil water uptake across soil depths were closely associated except at the surface or the ultimate soil depths of root presence.
RESUMO
Finger millet (Eleusine coracana L. Gaertn.) ranks third in production among the dry land cereals. It is widely cultivated in Africa and South Asia where soil salinization is a major production constraint. It is a potential crop for salt affected soils. To identify salt tolerant germplasm, the minicore finger millet germplasm (n=80) was screened for grain yield performance in a soil saturated with NaCl solution of 100 or 125mM. Genotype effect was significant for most traits, while salinity×genotype interaction was significant only in one year. Salinity delayed phenology, marginally reduced shoot biomass and grain yield. There was a large range of genotypic variation in grain yield under salinity and other traits. The yield loss was higher in accessions with prolific growth and yield potential was associated with saline yields. Based on saline yields, accessions were grouped in to four groups and the top tolerant group had 22 accessions with IE 4797 remaining at the top. Salinity had no adverse impact on grain yield of five accessions. Root anatomy in selected genotype of pearl and finger millet showed presence of porous cortex and well fortified endodermis in finger millet that can exclude Na(+) and enhance N absorption.
