Volume 9 No. 2 April – June 1987

Berta Catingan-Ratilla and Victor P. Briones ABSTRACT Application of nitrogen fertilizer up to 90 kg/ha with 30 kg each of P2O5 and K2O did not remarkably affect the growth and yield parameters of flint corn. However, visual observation indicated that fertilization resulted in the development of sturdier corn plants with darker green and broader leaves. …

Effects of Nitrogen Level and Row Spacing on the Growth and Yield of Flint Corn Read More »

Paz Saladaga-Eronico and Rodolfo G. Escalada ABSTRACT Generally, no significant differences in agronomic characters and yield components of sweet potato were observed using either the traditional methods or the recommended practice of planting. Varying the number of cutting per hill significantly influenced only the fresh vine weight of Kaimay, BNAS-51 and Samar Big Yellow sweet …

Comparative Evaluation of Traditional Methods and Recommended Practice of Planting Sweet Potato Read More »

Emmanuel M. Cabia and Eduardo Paningbatan ABSTRACT Date of planting significantly influenced growth and development of corn. Corn first planted on the last week of April and those planted 3 and 5 weeks later (May 16 and May 29) exhibited superior growth and ear yields over those planted 7 and 9 weeks later (June 12 …

Influence of Planting Date on Corn Grown in an Aquic Eutropept Read More »

Nestor L. Pido and Liwayway M. Engle ABSTRACT Inherent variations were observed in the lead shape of sweet potato cultivars Kinabakab and UPLB Acc. 624 and in the root skin pigmentation of BNAS-51 cultivar. Doses of 2000 and 3000 rads produced wrinkled and deformed leaves in vM1 plants of all three cultivars with the latter …

Effects of Gamma Radiation on Some Morphological Characters of Sweet Potato Read More »

Gracia B. Bajit and Ruben M. Gapasin ABSTRACT The morphological characteristics of sweet potato cultivars which are resistant and susceptible to Sphaceloma batatas Saw. were determined. Susceptible cultivars have thinner cuticle, more stomates in the leaves, and more lenticles in the petioles and stems than resistant cultivars. The scab pathogen had longer incubation period, lower …

Relationship Between Morphological Characteristics and Varietal Resistance of Sweet Potato to Scab Infection Caused by Sphaceloma batatas Saw Read More »

Manuel K. Palomar ABSTRACT Adults and nymphs of the taro planthopper, Tarophagus Proserpina Kirk., were equally efficient in transmitting taro feathery mosaic disease. Both the minimum acquisition feeding period and minimum inoculation feeding period were about 5 min. A single insect could induce the disease in a healthy plant and percentage infection increased as the …

Relationship Between Taro Feathery Mosaic Disease and Its Insect Vector, Tarophagus Proserpina Kirk Read More »

Tita L. Cayme and Dely P. Gapasin ABSTRACT The total developmental period of the coconut spider mite, Oligonychus velascoi Rimando was 6.3 and 6.9 days for those reared on detached and undetached leaflets, respectively. The slight difference observed in the life cycle of mites using the two rearing methods indicates that both techniques are satisfactory …

Biology, Host Range and Natural Enemies of the Coconut Spider Mite, Oligonychus velascoi Rimando Read More »