Rubber Science

CONTROL OF PATCH CANKER DISEASE ON HEVEA BRASILIENSISResearch Articles
Pages 149 - 153
Sadanand K. Mushrif, E. Edwin Prem & C. Kuruvilla Jacob
- Abstract
- Keywords
Five systemic and contact fungicides incorporated in a petroleum wound dressing compound were evaluated for the control of patch canker disease caused by Phytophthora spp. in the Hevea brasiliensis clone PB 260 in comparison with Bordeaux paste. Among them, mancozeb, metalaxyl+mancozeb, phosphorous acid and thiophosphate were found to be effective. However, considering consistency of disease control and the cost of treatments mancozeb is the fungicide of choice for the control of the disease.

Disease control, Hevea brasiliensis, Patch canker, Phytophthora spp

BLEACHING OF BROWNED WATER YAM (DIOSCOREAALATA) WITH RUBBER (HEVEA BRASILIENSIS) SEED LIPOXYGENASEResearch Articles
Pages 154 - 160
M.N. Anokwulu, O.U. Njoku & I.C. Ononogbu
- Abstract
- Keywords
Lipoxygenase was extracted from rubber (Hevea brasiliensis) seed, purifed and used to bleach the polyphenols in water yam (Dioscorea alata) tubers. There was increase in the percentage bleaching of polyphenol extracts (31.43 ± 0.11 to 89.43 ± 0.58) as the enzyme concentration and time of reaction increased. The polyphenol content in the browned yam cubes were observed to decrease (26.94 ± 0.08 to 19.52 ± 0.04 µg/g) as the enzyme concentration was increased (0.13 to 0.78 unit/ml). The concentration of rubber seed lipoxygenase required for complete bleaching of the browned yam cubes was 3.1 unit/ ml.

Bleaching, Linoleic acid, Lipoxygenase, Polyphenols, Rubber seed, Yam

EFFECT OF POTASSIUM AND MAGNESIUM INTERACTION ON SOIL PROPERTIES AND GROWTH OF IMMATURE HEVEA BRASILIENSIS IN ASSAMResearch Articles
Pages 161 - 171
R.P. Singh, D. Mandal, Mercykutty joseph, A.C. Sarma, C.K. Gupta & A.K. Krishnakumar
- Abstract
- Keywords
Two field experiments were conducted for eight consecutive years (1987-1995) at two locations in Assam to assess the influence of potassium and magnesium and their interaction on growth, yield and nutrient contents of rubber (Hevea brasiliensis). Girth and girth increment did not show significant improvement due to application of K and Mg but it significantly increased their contents in leaf and had synergistic effect on leaf N and P contents. Application of K significantly increased the availability of K. Also increased the availability of P and organic carbon content and reduced the availability of Ca and Mg. Similarly application of Mg improved the Mg availability as well as organic carbon and available P and Ca. Antagonism between K and Mg was expressed in soil as well as in leaf. Addition of K reduced the Mg availability in soil and Mg concentration in leaf. Conversely addition of Mg reduced the soil available K and leaf K concentration.

Growth, Hevea brasiliensis, Immature phase, Magnesium, Nutrients, Potassium, Soil characteristics

EFFECT OF POST-BUDDING PRACTICES ON ESTABLISHMENT AND GROWTH OF GREEN BUDDED PLANTS OF HEVEA BRASILIENSIS IN THE POLYBAG NURSERYResearch Articles
Pages 172 - 175
J.G. Marattukalarn, V.C. Mercykutty, C.K. Saraswathyamma, D. Premakumari & T.R. Chandrasekhar
- Abstract
- Keywords
The effect of delayed opening and delayed pulling out of budded plants of Hevea brasiliensis on budding success, establishment and growth of young plants was studied. Both delayed opening and delayed pulling out did not show any influence on the characters observed. Significant differences between treatments existed only for number of stock shoots produced. The practice of retaining longer snags and nicking of snag buds had no discernible advantage in the production of poly bag plants.

Green budding, Hevea brasiliensis, Polybag plants, Nursery practices

EVALUATION OF BOWL SLUDGE AS A SOURCE OF PHOSPHORUS NUTRIENT FOR HEVEA BRASILIENSISResearch Articles
Pages 176 - 182
Elsie S. George, K.I. Punnoose & M. Karthikakuttyamma
- Abstract
- Keywords
Field experiments conducted at two locations in Kerala, India to evaluate bowl sludge, a waste product from latex centrifuge factories, revealed its usefulness as a source of phosphorus nutrient for rubber (Hevea brasiliensis). The increment in girth and yield was comparable to that when super phosphate or mussoorie rock phosphate was used. Soil chemical properties were not affected by continued application though bowl sludge contained appreciable quantity of magnesium. Leaf and latex nutrient contents were also unaffected. The result of the study indicated bowl sludge as a potential source of phosphorus fertilizer for rubber plantations.

Bowl sludge, Hevea brasiliensis, Phosphatic fertilizers, Waste utilization

INTERACTION BETWEEN ENDOMYCORRHIZAL FUNGUS GLOMUS FASCICULATUM AND ROOT-KNOT NEMATODE, MELOID0GYNE INCOGNITA ON PUERARIA PHASEOLOIDESResearch Articles
Pages 183 - 187
S. Thankamony, R. Kothandaraman, C. Kuruvilla Jacob, Kochuthresiamma Joseph & V.T. Jose
- Abstract
- Keywords
Interactive relationship of the vesicular arbuscular mycorrhizae, Glomus fosciculatum and root-knot nematode, Meloidogyne incognita on Pueraria phaseoloides was studied. Mycorrhizal association enhanced total biomass as well as fresh root weight of plants while the nematode infection reduced them. Mycorrhizal colonization percentage and spore count was more when VAM was inoculated alone or prior to nematode inoculation. The reproduction factor of M.incognita decreased in presence of mycorrhizae. The inoculation of VAM induced tolerance in P. phaseoloides to M.incognita.

Meloidogyne incognita, Pueraria phaseoloides, Vesicular arbuscular mycorrhizae.