Md. Abdullah Al Mamun
Department of Agriculture Extension, Rangpur, Bangladesh
Abdullah-Al-Mahmud
Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh
Md. Shawquat Ali Khan
Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh
Md. Altaf Hossain
Bangladesh Agricultural Research Institute, Joydebpur, Gazipur, Bangladesh
Mohammad Zakaria
Bangabandhu Sheikh Mujibur Rahman Agricultural University, Salna, Gazipur, Bangladesh
Top shoot cutting, Planting date, Seed potato multiplication
Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur
Crop-Soil-Water Management
Location, Test Crop and Agro-Climatic Condition:Top-shoot cuttings were evaluated as planting material with different planting time for rapid multiplication of potato at Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU) during winter, 2011-2012. The location is situated at about 24023' north latitude, 90008' east longitude and an altitude of 8.4 m above sea level and adjacent to capital Dhaka city. Potato variety Diamant (BARI Potato-7) was used as test crop. During the growing period maximum and minimum air temperature, relative humidity (%), precipitation and evaporation data were recorded throughout the crop period. The air temperature was decreasing in trend from November to January and thereafter increased. Design and Treatment: The experiment was laid out in randomized complete block design (RCBD) with three replications. The treatments were: T1 = Whole tuber planting at 1st November (1st Control), T2 = Whole tuber planting at 1st November for cutting; T3 = 1st cutting from T2 planted on 25th November; T4 = 2nd cutting from T2 on 5th December; T5 = Whole tuber planting on 10th November (2nd control); T6 = Whole tuber planting on 10th November for cutting; T7 = 1st cutting from T6 on 5th December and T8 = 2nd cutting from T6 on 15th December. Seed Preparation, Planting of Tubers and Stem Cutting: The seed tubers were kept in a well-ventilated room and allowed to sprouting under light at night for obtaining healthy green sprouts prior to planting. In this process, 8 - 10 days were elapsed for sprouting. The sprouted tubers were planted at 1st November (T1 and T2) and 10th November (T5 and T6). T1 and T5 were treated as control for producing normal crop. Treatments T2 and T6 were used as source of top shoot cuttings. First top-shoot cuttings with at least two nodes were taken from T2 at 25 days after planting (DAP) which were used as planting material for T3. Second cuttings were taken from (T2) at 10 days after first cutting which were used as planting material for T4. Cuttings were taken by slant cut with a sharp blade and the cut end immerged into water immediately. Then the shoot cuttings were planted in the main plot after treating them with rooting hormone (Napthalene Acetic Acid-16 ppm). Before planting the shoot cuttings in the experimental plots, the plots were irrigated properly so that the cut portion came to the soil and moisture contact. Similarly the top-shoot cuttings were taken from T6 which were used as planting materials for T7 and T8 at 5th December and 15th December, respectively. Fertilizer Application: Full doses of cow dung (10 t ha−1), triple super phosphate (220 kg ha−1), muriate of potatsh (270 kg ha−1), gypsum (120 kg ha−1), boric acid (6 kg ha−1) and half dose of urea (175 kg ha−1) were applied at final land preparation. The rest half of urea (175 kg ha−1) was top dressed at 30 DAP followed by earthing up and light irrigation. Ridge method was used for whole tuber planting (T1, T2, T5 and T6) treatments. Intercultural Operation: Healthy top shoot cuttings were planted in well watered flat bed. After establishment of the shoot cuttings, ridge was made by earthing up of sides. Intercultural operations such as weeding and earthing up were done manually. Earthing up was done two times, first earthing up was done at 30 DAP when the plant attained a height of about 15 - 20 cm from the base, second time was done at 20 days after the first earthing up. Before the first earthing up, urea was applied. Irrigation was applied five times. The first one was applied at two weeks after planting, the second one was just after earthing up (30 DAP), the third one was at 45 DAP, the 4th one on 60 DAP, and the last one was at 75 DAP. During land preparation, Furadan 5G was applied 10 kg/ha as basal to control soil borne insects and Malathion (0.2%) sprayed in two installments at 45 and 60 DAP control foliar insects. Dithane-M 45 (0.2%) and Secure (0.1%) sprayed alternately five times at 30, 40, 50, 60, 70 DAP to prevent the late blight disease. Haulm pulling was done at 80 DAP in all treatments. Hardening and setting up of skins of tubers were allowed for 10 days under the soil and there after the crop was harvested at 90 DAP. Data Collection: Yield of Tubers: The gross yield of tubers per plot was recorded by taking weight of the harvested tubers from all plants of a unit plot and was converted into yield in tons per hectare by using following formula:
Yield (ton/ha) = [Tuber yield per plot (kg) ×10] / Area of plot (sq⋅m). Tuber Grade by Number (%): All the tubers from the randomly selected five plants were graded into four groups by number (under size ≤ 28 mm, Grade A = 28 - 40 mm, Grade B = 41 - 55 mm and Over size ≥ 55 mm) and expressed in percentage. By using the following formula percentage of each grade was calculated.
Tuber grade by number (%) = [(Number of tubers of particular grade) / (Total number of tubers)] × 100
Tuber Grade by Weight (%): All the tubers from the randomly selected five plants were graded into four groups by weight (under size ≤ 28 mm, Grade-A = 28 - 40 mm, Grade-B = 41 - 55 mm and over size ≥ 55 mm) and expressed in percentage. By using the following formula percentage of each grade was calculated.
Tuber grade by weight (%) = [(Weight of tubers of particular grade) / (Weight of tubers)] ×100. Data Analysis: Recorded data on tuber yield, grades of tuber by weight and by number were analyzed statistically using the software MSTATC (Developed by the Department of Crop and Soil Sciences, Michigan State University, East Lansing, MI 48824 USA). Significance between treatments were tested by using Duncan Multiple Range Test (DMRT) at p < 0.05 level. Benefit cost ratio (BCR) was calculated.
Open Access Library Journal, Volume-2: e1904; (2015)
Journal