M. A. Rouf
Senior Scientific Officer
Hill Agricultural Research Station, Khagrachari.
M. A. Rahim
Professor
Department of Horticulture, Bangladesh Agricultural University (BAU), Mymensingh-2202.
M. A. Siddique
Professor
Department of Horticulture, Bangladesh Agricultural University (BAU), Mymensingh-2202.
M. B. Meah
Professor
Department of Plant Pathology, BAU, Mymensingh-2202, Bangladesh.
Cauliflower; Curd scooping; Honey bee pollination; Seed production
Horticulture Farm of Bangladesh Agricultural University.
Seed Technology
The experiment was conducted at the Horticulture Farm of Bangladesh Agricultural University (BAU) during 2002-03. The land selected for the experiment was medium high land. Dhaincha ( Sesbania rostrata ) was grown during the kharif season before the cauliflower cultivation. The soil of the area belongs to the Old Brahmaputra alluvial tract under AEZ - 9 of Bangladesh and was silty loam in texture (sand 13.6%, silt 71.4% and clay 16.0%). The soil pH was 6.90. Mechanical analysis of the soil of the experimental field (0-30 cm depth) was performed in the Humbldt Soil Testing Laboratory, Department of Soil Science of BAU. The treatments consisted of three types of pollination viz., P0 = open (natural) pollination, Pb = using bees for pollination inside net (planned pollination) and C = plants inside net without bees (control) and six kinds of curd scooping viz., S1 = 25% or ¼ portion of a curd cutting, S2 = 50% or ½ portion of a curd cutting, S3 =75% or ¾ portion of a curd cutting, S4 = cross curd cutting i.e., 2mm breadth cutting on the curd just like a ‘X’, S5 = central curd cutting i.e., 2 cm diameter round cutting from the central portion of the curd and S0 = without curd cutting (control). So there were 18 treatment combinations in all. The mosquito net was used in the experiment. In case of treatment Pb, the unit plots were caged with mosquito nets along with honey bees ( Apis cerana L.) during flowering period. Bee hives of A. cerana were borne to every unit plots of Pb treatment and bees were allowed to go inside the net, a nd thereafter the net was closed. But in case of ‘C’ treatment, the unit plots were caged with mosquito net where no pollinators (honey bees) were allowed. Unit plots of P0 treatment were kept as natural open condition. The experiment was laid out in Randomized Complete Block Design with three replications.
The unit plot size was 3.0 m × 2.4 m accommodating 20 plants per plot with a spacing of 60 cm × 60 cm. The test variety was ‘Poushali’ which is an open pollinated (OP) variety. Forty day - old seedlings were transplanted on 25 October, 2002. The land was fertilized by well decomposed cowdung with doses 20 t/ha, and N, P, K, B and Mo with 68, 50, 110, 3 and 0.78 kg/ha. The sources of N, P, K, B and Mo were urea, TSP, MoP, borax and sodium molybdate. The whole amount of P and half of the cowdung were incorporated to the soil during final land preparation and the remaining half of cowdung and one - third of each N and K were applied to the pit while the rest of N and K were top dressed in two equal installments at 21 and 45 days after transplanting. One additional dose of N (45 kg/ha) and MoP (50 kg/ha) was applied during flowering of cauliflower. The crop after transplanting was irrigated daily by a watering can up to 6 days and then twice a week and later once a week. The crop was irrigated within 3 - 4 days of mulching and fertilizer application. Excess water during the rain was drained out to avoid water stagnation. The other intercultural operations and plant protection measures were taken as and when necessary. The seed crop was harvested on 2 - 5 April, 2003. Data were taken on days to 50% flowering, days to siliqua maturity, number of primary and secondary flower stalks/plant, number of siliquas/plant, length of siliqua (cm), number of seeds/siliqua, 1000 seed weight, seed germination (%), seed yield/plant (g) and seed yield/ha. The data were taken randomly from 10 plants of each plot. After seed harvest, seed germination test was done in the laboratory of the Horticulture Department of BAU. Data were analyzed by using statistical package programme MSTAT - C. Mean separation was done by Least Significant Difference (LSD) test at 5% level of probability.
Bangladesh J. Agril. Res. 41(2): 251-258, June 2016, ISSN 0258-7122
Journal