DILTA, B.S.THAKUR, PRIYANKA2018-05-152018-05-152018-03http://krishikosh.egranth.ac.in/handle/1/5810045578ABSTRACT The present investigation entitled, “Influence of planting dates, mulches and GA3 applications on seed yield and quality of African marigold (Tagetes erecta L.) cv. Pusa Narangi Gainda” was carried out at the Khaltoo experimental farm of Department of Seed Science & Technology, Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan (HP) during 2015 to 2017. The experiment was laid out in Split- Plot Design with 48 treatment combinations of three planting dates (viz., 1st July , 16th July and 1st August), four levels of mulching ( no mulch, crop residue mulch, black plastic mulch and silver-black plastic mulch) and four doses of GA3 (0, 50,100 and 150 ppm ) replicated thrice. Planting of seedlings was done at three different planting dates along with application of different mulches and the treatments of GA3 were applied after 45 days of transplanting as foliar spray. The data were recorded on various growth, flowering, seed yield and quality attributes and subjected to analysis of variance. The results obtained indicated that transplanting of seedlings in the 1st week of July (1st July), mulching of plants with silver-black sheet (M4) and spraying of plants with the highest concentration of GA3 (i.e. 150 ppm) alone as well as in combinations exhibited best performance in terms of minimum days taken to first flowering (days) and attaining maximum values w.r.t. plant height (cm), number of flowers per plant, size of flowers (cm), shoot fresh weight (g), shoot dry weight (g), root fresh weight (mg), root dry weight (mg), number of seeds per head, seed yield per plant (g), seed yield per plot (g), 1000 seed weight (g), germination percentage (%), seedling length (cm) and dry weight (mg), seed vigour index-I (Length) and seed vigour index-II (Mass) as well as lowest electrical conductivity of seeds (dS/m) in comparison to all other treatments. Therefore, transplanting of seedlings be commenced on in 1st week of July (1st July) and mulched with silver- black plastic sheet (M4) along with spraying of GA3 @ 150 ppm after 45 days of transplanting can be recommended for commercial seed production of marigold under mid hill conditions of Himachal Pradesh.enSEED SCIENCE AND TECHNOLOGYThesis