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Current study aims to explore natural anti-phytopathogenic compounds for plant disease management. Syzygium cumini essential oil and its isolated compounds were screened for their antifungal assay against two phytopathogenic fungi, Rhizoctonia solani AG 4HG-III and Choanephora cucurbitarum . The chemical composition of oil the isolated oil was identified by gas chromatography and gas chromatography/mass spectrometry. Compounds such as 7-hydroxycalamenene, 7-acetoxycalamenene, 1-epi-cubenol, and α-terpineol showed an inhibition, ca. 95%, 80%, 76%, and 82%, respectively, against R . solani whereas 95%, 70%, 92%, and 100% against C . cucurbitarum in contact phase. In addition, high ocimene rich column fractions showed 70% and 87% inhibition against R . solani and C . cucurbitarum , respectively, in volatile phase. The findings of the present study suggest that the isolated 7-hydroxycalamenene, 7-acetoxycalamenene, 1-epi-cubenol, α-terpineol, and ( Z )-β- & ( E )-β-ocimene have a potential to be used as antifungal agents for the effective control of fungal diseases in medicinal plants. We report 7-acetoxycalamenene as novel compound from natural source for first time.

A good extent of variation was observed for all the traits among 41 accessions of Ammi visnaga. Morphological variability for stem colour and umbel mutant with centre red to pink was detected. Maximum GCV and high heritability and genetic advance as percentage of mean were observed for biological yield followed by harvest index, seed yield, which may provide good amount of advance expected from selection because these traits may be possibly governed due to additive gene effects. The genotypic correlation in general, was higher than phenotypic; positive significant correlation was observed between seed yield and number of primary branches, harvest index; biological yield and number of umbel, number of primary branches. A high direct positive effect on seed yield was of biological yield followed by harvest index and primary branches. Therefore, composite populations through poly-cross nursery of desired accessions and recurrent selection recommended for genetic improvement in Bishop's weed.

Forty genetic stocks of vetiver (Vetiveria zizanioides L. Nash) were screened for high oil yield. The considerable amount of natural and genetic variability in morpho-metric traits was recorded. The estimate of heritability (^h2BS %) and corresponding genetic advance (GA), both were high for plant height (^h2BS % = 98.48 and GA = 64.83). Genetic (G) and phenotypic (P) associations coefficients among the seven traits indicated that plant height was highly and significantly correlated with tillers/plant (0.399**G, 0.389**P); fresh root with dry root yield (0.905**G, 0.769**P) and oil content with oil yield (0.397**G, 0.390**P) at both genotypic and phenotypic level. The plant height with root length was also positively correlated with each other at both genetic (G) and phenotypic (P) levels (0.282*G, 0.278*P). The path coefficient under study revealed that the highest direct contribution to total oil yield was made by fresh root yield (0.514) followed by oil content (0.386), tillers/plant (0.149) and root length (0.086) in percent.