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1978 - 197911980 - 19861
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Subject: Horticulture × Author: Nybe, E V × End date: 1995 ×
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    ThesisItemOpen Access
    Morphological studies and quality evaluation of ginger (zingiber officinale rosco) types
    (Department of Horticulture (Plantation Crops), College of Horticulture, Vellanikkara, 1978) Nybe, E V; KAU; Sivaraman Nair, P C
    A detailed study of 25 ginger types was conducted during the period from April 1977 to June 1978 at the College of Horticulture, Vellanikkara with a view to find out the feasibility of fixing up specific morphological characters to identify different types, to screen out ginger types with high yield, high quality and resistant or tolerant to pests and diseases and to study the quality variations at different periods of maturity. The study revealed that morphological characters are not reliable to classify the ginger types, although some of them can be identified by rhizome characters. The morphological characters such as length of leaf, leaf area index and number, length and girth of primary and secondary fingers were found to be positively correlated with yield. All the types studied are susceptible to the incidence of soft-rot, leaf –spot and shoot-borer. The type Maran was relatively tolerant to soft-rot whereas Rio-de-Janeiro was found to be the most susceptible type. Yield was found to vary significantly among the types studied. Maximum yield was recorded in Nadia followed by Bajpai, Maran and Narasapattom. Maximum oleoresin percentage was in Rio-de-Janeiro and highest percentage of oil recovery in Karakal. But the maximum yield per hectare of oleoresin and oil was in the type Maran. Fibre content was minimum in China and maximum in Kuruppampady closely followed by Maran. The yield, dryage and percentage of oleoresin, oil and crude fibre varied significantly among the different maturity periods studied. The percentage of oleoresin, oil and fibre was maximum at 165 days after planting. But the maximum yield per hectare of oleoresin and oil were found at 270, 195, 225 and 225 days after planting in Rio-de-Janeiro, Maran, Kuruppampady and Wynad Local respectively. Cultivation of the types Nadia, Bajpai and Maran is recommended for higher total yield of dry ginger for the plains of Kerala. Considering the low incidence of soft – rot and higher yield of oleoresin and ginger oil the type Maran is preferred
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    ThesisItemOpen Access
    Investigations on the nutrition of black pepper (Piper nigrum L.)
    (Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 1986) Nybe, E V; KAU; Sivaraman Nair, P C
    Detailed studies were conducted in black pepper (var. Panniyur 1) from 1981 to 1985 at the Pepper Research Station, Panniyur and College of Horticulture, Vellanikkara with a view to induce nutrient deficiency symptoms by sand culture and to find out the relationships of foliar nutrients with yield. Deficiency symptoms of macro-nutrients except Ca and S were first manifested on the older leaves while that of micro-nutrients on younger leaves. Symptoms of N deficiency were expressed as uniform yellowing followed by necrosis whereas purple to bronze yellowing with ash coloured necrotic areas were the symptoms of P deficiency. Potassium deficiency symptom was characterized by tip and marginal necrosis which later progressed to the two-thirds distal portion of the lamina. Calcium deficiency symptoms appeared as tiny brown necrotic spots on chlorotic area near margins which later enlarged to form black necrotic areas. Visible symptom of Mg deficiency was oval interveinal chlorotic area followed by black necrotic patches. Sulphur deficiency was manifested as uniform yellowing with brown necrotic spots. There was profound reduction in vegetative growth due to deficiency of macronutrients. The reduction in shoot growth and leaf area index was maximum in the case of deficiency of N (56 and 63% respectively) followed by S (48 and 17% respectively). The reduction in root growth was quite high due to deficiency of Ca (61%), P (45%) and N (39%). Interveinal chlorosis was the initial symptom of deficiency of all micro- nutrients. However, the symptoms were specific to the concerned nutrients. Iron chlorosis was characterized by the presence of green bands along the major veins whereas bronze yellow colour of the interveinal areas was the specific symptom of Mn deficiency. Bronze colour of the entire lamina with necrotic tips and margins were the symptoms of Cu deficiency. Zinc deficiency was unique with little leaf and rosetting. Due to B deficiency, the leaves became large, thick and brittle with orange yellow mottles on upper surface and grey brown interveinal patches on lower surface. Unlike macronutrients, there was no marked reduction in vegetative growth due to deficiency of micro-nutrients except Fe and B which recorded 35 and 22 per cent reduction respectively, in total dry matter production. Boron deficient plants registered 18 per cent increase in leaf area index. The growth of the vine was completely arrested at comparatively early stage (4.5 months after treatment) due to S deficiency followed by N (6th month), Fe (7th month), B (12th month), P (13th month) and Cu (14.5 months after treatment). There was no cessation of growth in the case of deficiencies of other nutrients. Visual symptoms of deficiencies were concurred with a marked reduction in the foliar levels of the concerned elements. Antagonistic effects among K, Ca and Mg were also observed. In all other cases, deficiency of one element failed to influence the foliar level of others. The deficiency symptoms could be recovered by the application of the deficient nutrient element which provided valid information for the confirmation of the deficiency symptoms. The foliar levels of macro-nutrients except Ca registered two peaks, one in June and the other in October while the lowest level was during April. The nutrients namely Ca, Fe, Mn and Zn, in general showed a decreasing trend from April to June and thereafter increased and reached maximum level in December. Highly significant positive correlations were showed by P, K, Ca and Mg with yield. The critical level of S was found to be 0.15%. The ‘tentative critical levels’ suggested for the other elements studied are as follows: N - 2.1 to 2.4% P - 0.19 to 0.20% K - 1.8 to 1.9% Ca- 2.8 to 2.9% Mg - 0.5 to 0.6% Fe - 156 to 169 ppm Mn - 77 to 88 ppm Zn- 30 to 32 ppm The two most important nutrient elements which are highly essential for the production of pepper could be identified as K and P in view of their high direct and indirect effects on yield.