No abstract

The germplasms of African and French marigold were screened at Research Farm Area, Department of Horticulture, CCS Haryana Agricultural University, Hisar, Haryana against the two spotted spider mite, Tetranychus urticae (TSSM) in the winter season from first week of October to first week of March, 2018. The germplasm tall orange African sheltering lowest mite population (9.82 mites/leaf) was marked as the least susceptible and Hisar Jafari-2 French with 32.21 mites/leaf was categorized as highly susceptible for T. urticae infestation. Mite population was recorded weekly and significantly higher number of mites was recorded on grown up leaves followed by tender and older leaves of marigold plants. Irrespective of the germplasm, the mite number was found to significantly increase with each observation period till the attainment of peak in population in the month of January (35.51 mites/ leaf) while their least population was recorded in the month of October (6.65 mites/leaf). In general, French germplasms were comparatively more susceptible to T. urticae infestation as compared to African germplasms.

Melia composita (Burma dek) is one of the multipurpose fast growing tree species applicable for the agri-silviculture system. In northern India, due to its fast growing and short rotation nature it has developed one of chosen tree species by the farmers under agroforestry. Melia composita occurs mostly in tropical moist and dry deciduous forest of Himalayas. The seed have Hard endocarp and therefore quite difficult to germinate. There are different types of seed dormancy and it helps in find out the better pre-sowing treatment to assure early and uniform germination of seeds. This leads to minimize the cost of large scale seedlings production. The present study was conducted at Laboratory of Seed Science and Technology, CCS Haryana Agricultural University during 2019 to evaluate the “Effect of pre-sowing treatments on seed germination of Melia composita”. Five pre-sowing treatments viz., normal water soaking (24, 48 and 72hr), conc. H2SO4 (5, 10 and 15 min.), cow dung slurry (5, 10 and 15 days), boiling water (5, 10 and 15 min.), mechanical scarification + GA3 (100 ppm) (8, 16 and 24hr). In laboratory conditions, maximum germination (64.67 %) and seed viability (74.67%) were recorded in concentrated H2SO4 treatment at 15 minute, whereas maximum root length (7.54 cm), shoot length (16.72 cm), root: shoot ratio and seedling dry weight (0.65g) were recorded in mechanical scarification + GA3 (100 ppm) at 24 hr.

Mung bean is a short-duration ancient legume crop that can be grown as a sole or intercrop for grain and green manure in all three crop seasons, including winter, summer and rainy in various regions of the country. MYMV (Mungbean Yellow Mosaic Virus) disease is one of the most destructive diseases transmitted by whitefly (Bemisia tabaci Genn) persistently. Weather parameters have no direct effect on MYMV, but affect the whitefly population. Field experiments were conducted for three consecutive years from 2019-2021 as to know the effect of weather parameters on the whitefly population. Development of whitefly population and MYMV disease severity were recorded in mungbean crops at 7 days interval starting from 20 days after sowing (DAS). The present study showed that whitefly population builds up starting in July and reached to maximum at end of August to early September. There are various factors influencing the build-up of whitefly population viz., maximum temperature 36±2°C, minimum temperature 25±2°C, morning relative humidity more than 90 percent, more sunshine hours and no rainfall prevailing during that period. Whitefly population had positive significant correlation with maximum temperature and bright sunshine hours while evening relative humidity and rainfall were recorded as negatively significant. Three-year data is very helpful in guiding the farmers for timely and preventive sprays based on existing infections and the population of whitefly in a season.

Researchers are very concerned about addressing or managing the growing problem of global warming or climate change. Global warming is caused by greenhouse gases, of which carbon dioxide (CO2) alone contributes 60%. By absorbing carbon dioxide (CO2) during photosynthesis and naturally storing it as biomass, trees serve as a sink for CO2 because trees have the ability to store carbon and can lessen the effects of climate change and global warming, planting trees or restoring forests may be a solution to this growing problem. This review paper can be helpful since it discusses the interaction between arbuscular mycorrhizal fungi (AMF) and the roots of trees, which benefits the plant for better germination and growth. dormancy of seeds or a delay in growth can be identified as a disadvantage in a plantation program. With the hope that this information would advance the field of research, we have concentrated on mycorrhizal association and its impact on different species of trees in this work. It can be useful for tree species that have lower biomass or slower growth.