Germination, Rhizome survival and control of imperata cylindrica (L) beauv. on peat
S.A.Lee
Abstract
Imperata cylindrica seeds had a germination of 84.5% after 3 weeks under alternating temperatures of l5/350C. Each parent shoot produced 181.3 shoots after 61/2 months in the field. After l21/2 months, 71.9% of the rhizomes occurred in the surface 15 cm of soil while the remaining 28.1% occurred between l5 and 30 cm. The study of the pattern of rhizome growth showed that a young rhizome network is established after l0-l4 weeks with 2-4 rhizomes below each locus of shoots. The factorial experiment on the depth of burial x rhizome length showed that rhizomes buried at 10 cm or more did not germinate. Glyphosate at 2.5-3.7 kg/ha provided very effective control for 5 months. Of the three additives studied for synergistic effects with glyphosate,only sulphate of ammonia appears promising.
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Seasonal fluctuations in oil palm leaf nutrient levels
H.L. Foster and Chang Kwong Choong
Abstract
Seasonal fluctuations in the concentration of nutrients in leaf 17 of oil palms were examined in relation to changes in rainfall, soil moisture, yield level and time of fertilizer application, in 19 oil palm fertilizer trials carried out in West Malaysia. On coastal soils, leaf P and K were found to increase with the average level of soil moisture prior to sampling,whilst on inland soils, leaf K and Ca were found to decrease with the average rainfall received prior to sampling and leaf Mg decreased with the yield level prior to sampling. Equations are presented which can be used to correct for these leaf nutrient fluctuations.
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Establishment of leucaena leucocephala on the acidic inland soils of peninsular Malaysia-Effects of lime, inoculation, pelleting and phosphorus on the establishment of L. Leucocephala
Tham Kah Cheng, Wong Choi Chee and Ajit Singh Sidhu
Abstract
Pot and field studies to investigate the effects of lime, inoculation and lime-pelleting of seeds on the establishment of I. leucocephala were carried out. In addition, ClRP pelleting and phosphorus treatments were included in the field study. Under pot conditions, both the introduced cultivars gave significantly, higher yield than the local cultivar, but all cultivars showed similar responses to all the treatments. On the Serdang Series,liming and inoculation significantly increased yield under pot and field conditions. A similar response was observed on the Bungor Series under pot conditions. Lime-pelleting of inoculated seeds in the presence of lime significantly, increased yield by 39-fold under field conditions but appeared to depress yield under pot conditions. A similar depression of yield was observed on the Bungor Series under pot conditions. ln addition to lime, inoculation and lime-pelleting adequate phosphorus was also required to give optimum yield. Dry matter yield and nodule number were significantly correlated on both the Serdang (r=0.74**) and Bungor (r=0.70**) Series.
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Insects associated with collapsed pineapple fruits, heart rot plants and inflorescences
W.H. Lim and P.H. Lowings
Abstract
Pineapple fruits attacked by Erwinia chrysanthemi Burkholder et al. frequently attracted large populations of the souring beetles, predominantly Carpophilus foveicollis Murr. and Haptoncus luteolus Er. Ants, mainly Pheidole sp., Iridomyrmex sp. and Tapinoma sp. and flies, mainly Gymnonerius p.,Drosophila sp. and Atherigona sp. were also attracted but to a lesser extent. These insects,including the larvae of Atherigona orientalis Schin.Graptomyza brevirostris Wied and Thressa incongruens Beck were also found on heart rot tissues. Among the insects found on open pineapple flowers, the point of bacterial entry, ants were the most widespread and abundant. The habits of the more important insects and their roles as possible carriers of the disease are discussed.
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Studies in the intake and digestibility of two Varieties (Serdang and Coloniao) of guinea grass (Panicum maximum) by goats and sheep I. Long grass
C. Devendra
Abstract
A study is reported on the intake and digestibility of two varieties of Guinea grass (Panicum maximum) var. Serdang and Coloniao fed in the long form in balance studies using goats and sheep. Five balance studies for each variety were completed, each lasting for 21 days, a 14-day adaptation period being followed by a 7 day collection period. The grasses were fed at five stages of growth: 16-19, 21-28, 28-35, 35-42, 42-49 days. The chemical composition of the grasses decreased with increasing maturity due to growth. The crude protein contents on dry matter basis were 21.8 and 20.0, 16.7 and 16.7, 13.2 and 14.7, 12.5 and 14.5 and 11.5 and 11.9 per cent for Serdang and, Coloniao at the five stages of growth respectively. The corresponding gross energy contents on dry matter basis were 16.8 and 16.9, 16.6 and 16.5, 16.5 and 16.4, 16.1 and 16.1, and 14.9 and 16.1 MJ/kg. respectivelyth; the chemical composition was higher in vat. Coloniao compared to Serdang. Statistically significant difference were noted (P<0.05) between species between trials and interaction in the daily voluntary dry matter intake of fresh grass and dry matter. For both grasses goats recorded a higher digestibility of the proximate components compared to sheep. The digestibility of dry matter for goats and sheep for var.Serdang were 73.0 and 70.4, 68.3 and 66.7, 69.1 and 66.5, 69.7 and 65.6, 66.7 and 62.1, and for var. Coloniao 74.6 and 68.8, 72.4 and 68.4, 72.1 and 64.1, 64.3 and 60.0 and 61.2 and 58.5 per cent at 16 19 days stage of growth. Statistically significant differences (P<0.05) between goats and sheep were only noted for var. Coloniao in dry matter digestibility at 28-35 days growth. By comparison,for var. Serdang,significant differences (P<0.05) were noted in nitrogen-free extract at 21-28, and crude fibre digestibility at 35-42 and 42-49 days growth respectively.The results demonstrate a higher digestive efficiency in goats compared to sheep. The digestible energy (D.E.) content in the grass varieties were 6.70 to 10.19 (MJ/kg.) 4.19 and 7.37 (MJ/kg.) and D.C.P. values 1.0 to 2.3 per cent and 1.4 to 2.8 per cent for goats and sheep respectively. These suggested that at the five stages of growth studied,both varieties of grass had adequate D.E. to support maintenance and some production, while the N requirements for maintenance would only be adequate from the grass varieties up to 35 days growth. It is suggested that with increasing maturity of the grass, goats tend to digest the crude fibre component much better than do sheep.
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