Responses of Five Cassava Varieties on the Vegetative Growth Parameters to Organic and Inorganic Fertilizer.

Abstract

Cassava (Manihot esculenta) Euphorbiaceae is a woody shrub, and a very important food crop in the tropics. Cassava farmers prefer to raise their seedlings from stem cuttings for their desired cultivars instead of seeds. This is because; raising seedlings with seeds is not of immediate economic value. However there is need to involve the seeds for desired cultivars before the multiplication through stem cuttings, because Hybridization work depends upon seed germination. There appears to be insufficient information on the effect of organic and inorganic fertilizer on the vegetative growth performance of some cassava varieties. Therefore this study was conducted to improve upon the germination of seeds and to determine the effect of some organic and inorganic fertilizer on the vegetative growth performance, yield of seedlings of cassava varieties. Seed from five cassava varieties (IITA-TMS- IBA980505, IITATMS-IBA0110368, IITA-TMS-IBA30572, IITA-TMS-070593 and IITA-TMS-TMEB419) were
collected from International Institute of Tropical Agriculture (IITA) Ibadan, Oyo state. Viability test of seeds were carried out using floatation method. Seeds were then subjected to some pre-treatments including ordinary water, hot water and concentrated sulphuric acid. Seedlings were raised in a 25 cm by 20 cm black polythene bags at the Pure and Applied Botany Screen house of Federal University of Agriculture Abeokuta. Seedlings were subjected to 0.2 g and 0.5 g Nitrogen Phosphorus Potassium
fertilizer (NPK), cow dung and compost treatment separately at 8 weeks after planting. Treatments were replicated three times in a complete randomized design. Growth parameters measured induced plant height, leaf area (LA), number of leaves, number of nodes and internodes, leaf dry weight and leaf fresh weight. The relative Growth Rate (RGR), Net Assimilated Rate (NAR) and Leaf Area Ratio (LAR) of the seedling were also determined. The data obtained in the study were subjected to Analysis of Variance and means separated by Duncan’s Multiple Range Test at P ≤ 0.05. Results showed that Normal water treatment enhanced germination of seed most (70 %) in all varieties. The highest value in plant height and number of leaves were obtained in IITA-TMS-IBA070593 varieties with mean values of 83.67±20.17cm and 7.67±0.67cm when supplemented with 0.2 g and 0.5 g cow dung treatments. Highest values in internode were recorded in IITA-TMS-IBA070593 varieties with mean value 23.33±2.84 when
supplemented with 0.2 g cow dung treatment. Highest value of the node were obtained in IITA-TMSIBA30572 with mean value of 25.33±1.45 with 0.5 g NPK at 16 WAP, the highest value of LA were obtained from IITA-TMS-TMEB419 with 94.00±1.15 with 0.5 g cow dung. Highest RGR (0.72 gg-¹ week)and LAR (7121.42) cm²g-¹ were recorded in IITA-TMS-IBA30572, treated with 0.2 g cow dung, while highest NAR (0.56g-¹ week-¹) were recorded in IITA-TMS-IBA070593 treated with 0.5 g cow dung.