THE EXPRESSION OF THE YIELD-POWER AND THE DISEASE RESSISTANCE OF YUSU NO.1, A NEWLY-EVOLVED HIGH QUALITY VARIETY OF Ipomoea batatas
Zhang Qitang Li Kunpei Chen Dingfu(Southwest China Teachers University)
This paper gives an introduction of the result to appraise the yield-power and the resistance to Ceratocystts ftmbriata Ellis et Halsted of Yusu No. l, a newly-evolved high quality variety of Ipomcea, batatas. The average value in the fresh tuberous root weight of Yusu No. l was l 795. 5 kg/mu, the highest was 3 250. 0 kg/mu. Its mean yield iu dry matter is 588.7 kg/mu. the starch 413. 7 kg/mu. the fresh vine 2 286. 5 kg/mu. and total of fresh vine and tuberous root 3 905. 9 kg/mu. These yield-powers were 24.86%' 72.02%. 3'5.45% and 6.15% higher than those of Nongdahong respectively. In respect of resistance to Ceratccystis fimbriata Ellis et Halsted, the diseased scars of tuberous root in Yusu No. l were smaller diameter than those of tuberous root in Xushu 18 and it was shallower depth than those of tuberous root in Nongdahong and Xushu 18 through appraisal by using artificial inoculation. Furthermore, the rotting rate of tuberous root by the infection in Yusu No. l was lower than that in Nongdahong and Xushu 18 during the storage period.