Browsing by Author "Balachandran, P V"

Now showing 1 - 15 of 15

Dynamics of the absorption of forms of N by crops plants
(Department of Agronomy, College of Horticulture, Vellanikkara, 1995) Retheesh, P K; Balachandran, P V
An investigation was conducted at the Radiotracer Laboratory, College of Horticulture, Vellanikkara in the year, 1993 which consisted of two parts. In the first part absorption of different forms of nitrogen relative to its concentrations at different growth stages of rice was studied using labelled and non-labelled fertilizers. To know the molecular absorption of urea 14C-labelled urea fertilizer was used and the presence of 14C in the plant was taken as an evidence for the absorption of molecular form of urea. In the case of ammoniacal and nitrate forms of N, 15N-labelled and non-labelled materials were used alternately to find out the preferential absorption. In the second part of the investigation an attempt was made to know the possibility of molecular absorption of urea by a few selected plantation crops. The uptake of N and dry matter production were higher when rice plants were supplied with a combination of ammonium and nitrate in equal proportions. Among the three forms of nitrogen supplied at different combinations, nitrate N recorded the highest uptake when present along with urea N or ammoniacal N or both. Though the presence of urea had a repressing effect on the uptake of nitrate, ammonium enhanced the nitrate uptake. The uptake of nitrate N was more in the presence of ammonium than in its absence. With respect to ammonium uptake it was found that urea and nitrate had more or less similar influence on it. It was seen that rice plants absorbed molecular form of urea even in the presence of other readily available forms of nitrogen. The molecular absorption of urea by rice plants was found to vary from 12-18 percentage of the total N uptake. When urea was supplied along with ammonium and or nitrate the uptake of urea was found reduced. The quantity of urea absorbed by the plantation crops was found negligible and ranged from 0.5-3.3 µg per g of the plant dry weight.
Effect of application of zinc and copper on the yield of rice
(Kerala Agricultural University, 2000) Usha Mathew; Beena, C; Balachandran, P V
Estimation of heterosis in bhindi [Abelmoschus esculentus (L.) Moench]
(Department of Plant Breeding, College of Agriculture, Vellayani, 1984) Balachandran, P V; Manikantan Nair, P
Influence of high background radiation on coconut nutrition
(Department of Agronomy, College of Horticulture, Vellenikkara, 1998) Rekha, C; Balachandran, P V
An investigation on the influence of high background radiation on coconut palms was conducted during 1994-97 at the College of Horticulture, Vellanikkara. This study was carried out in the high background radiation areas of the coastal Kollam district. A pot culture experiment was also conducted at the College of Horticulture, Vellanikkara. Soil collected from the high background radiation area (Chavara) was used for the study. The radiation exposure of coconut roots and its influence on the root activity of coconut palms, radiation profile of coconut rhizosphere, radionuclide accumulation by coconut palms and the influence of organic matter application on absorption of radionuclides by coconut palms were assessed. The main findings are given below. A wide variation in natural background radiation ranging from 200-8 200 nGy h-1 was observed in Chavara and adjoining areas. The radiation levels were generally higher in the coastal areas compared to the inland. 232 Th was the major radionuclide contributing to the high radiation and its content in soil ranged from 144 to 3580 ppm. The results from root exposure studies indicated that plant roots are continuously exposed to high radiation levels and a significant reduction in radiation exposure occurred only at a depth of 1 m. Correlation and regression analyses revealed a significant positive relation between surface radiation and the radiation exposure at different soil depths. The root activity studies employing 32P soil injection technique revealed that the root activity of coconut palms in the high radiation areas was comparable with that in the low radiation areas. The studies on 232Th uptake and its distribution within coconut palm pointed out that considerable accumulation of the absorbed 232Th occurs in roots and that only a small fraction of it is translocated up to the leaves and nuts. Application of organic matter, especially green leaf manure was found to be highly effective in reducing the 232Th uptake by coconut seedlings growing in monazite rich soil.
Methane emission from wetland rice fields of Kerala
(Department of Agronomy, College of Horticulture, Vellanikkara, 2003) Reena Mathew; Balachandran, P V
Molecular absorption of urea by flooded rice
(Department of Agronomy, College of Horticulture, Vellanikkara, 1992) Safeena, A N; Balachandran, P V
An investigation on molecular absorption of urea by flooded rice was conducted at the Radio Tracer Laboratory , College of Horticulture, Vellanikkara, during the period 1990-1992. The effect of soil submergence on soil urease activity was also studied on five different soils of Kerala namely, laterite, kole, kari, kayal and black soils. An attempt was also made to develop an isotope method for urease estimation using 14c labelled urea . From the specific activity of 14c urea solution initially added and the count rates obtained for the KCI-PMA extract, the urea hydrolysis rate was calculated.
Nitrate reductase activity in cocoa (Theobroma cacap L.)
(Department of Agronomy, College of Horticulture, Vellanikkara, 1991) Rekha Bhaskar; Balachandran, P V
Nitrate reductase activity in black pepper (Piper nigrum L.)
(Department of Agronomy, College of Horticulture, Vellanikkara, 1990) Mini Thomas; Balachandran, P V
An investigation on the nitrate reductase activity in black pepper (Piper nigrum L.) was conducted at the College of Horticulture, Vellanikkara during the. period 1989-1990. Six varieties of pepper vines from the Pepper Research Scheme, Vellanikkara were used for the study viz., Panniyur-1, Karimunda, Kottanadan, Kuthiravali, Uthirankotta and Cheryakaniakadan. Seasonal and genotypic variations in NRA and NRA in different parts of pepper vine were studied. The effect of NO3-N and light on NRA were also investigated. Heritability of NR, heterosis and relationship between NRA and yield were also worked out. In Panniyur-1 fairly high NRA was noted in June which declined till September and increased and peaked in February. Significant positive correlation between NRA and NO3 content was obtained in all months except in February. The six varieties of pepper were brought under two groups based on the pattern of NRA. One group comprising of Karimunda, Kottanadan, Kuthiravali and Uthirankotta. The second group comprised of Panniyur-1 and Cheryakaniakadan. The mean leaf NRA in the different parts of pepper followed the order, runner shoot y plageotrope orthotrope y flag leaf > berry. There was significant increase1 in NRA with increase in NO3-N levels in both Panniyur-1 and Karimunda. In general NRA increased with increase in light intensity. NRA at 60 and 100 per cent light were superior to that at 10 and 30 per cent light in Panniyur-1. In Karimunda NRA at 30 and 100 per cent light were found to be superior to that at 10 and 60 per cent light intensity Heritability in the broad sense of NR was found to be low in blacK pepper. Relative heterosis in Panniyur-1 was 26 per cent while heterobeltiosis was 23 per cent. Significant positive correlation was observed between mean NRA and yield-in Panniyur-1.
Package of practices recommendations: crops- 2011
(Kerala Agricultural University, 2011) Balachandran, P V
Phosphorus nutrition of green gram
(Kerala Agricultural University, 1991) Balachandran, P V; Sasidhar, V K
Root level interactions in coconut cocoa system
(Department of Agronomy, College of Horticulture, Vellanikkara, 1996) Vandana Venugopal; Balachandran, P V
An investigation was undertaken at the Kerala Agricultural University during 1994-96 to study the root level interactions in pure and mixed stand of coconut and cocoa. The study was also aimed to assess the extent of soil nutrient depletion in coconut-cocoa systems. The seasonal effects on the root activity of coconut was also assessed. The most important findings of the investigation are abstracted below. Absorption of soil applied 32P did not differ in pure and mixed stand of coconut and cocoa. Coconut was a surface feeder in both cropping situations where the active roots were concentrated upto a depth of 30 cm. 32P uptake was not much influenced by lateral distance or depth of placement of radiolabel in pure and mixed cocoa. Maximum root activity was noticed at 30 cm depth in both pure and mixed stand of coconut. The lateral spread of the roots was more or less uniform upto a distance of 275 cm in both sole and mixed stand. Cocoa also was a surface feeder with active roots distributed uniformly upto a depth of 60 cm. Majority of the roots traverse a horizontal distance of 175 cm in sole and mixed cocoa. The available Ca, Mg and S were markedly high in mixed coconut whereas organic carbon, available Fe and Mn were high in sole coconut. Available P, K, Zn and Cu were more or less uniform in both sole and mixed stand of coconut. The organic carbon, available K, Ca, Mg were significantly high in soils of mixed cocoa whereas available Fe, Mn and Cu were more in soils of sole cocoa. Available P, S and Zn were in more or less same concentration in soils of both sole and mixed cocoa. The 32P uptake was higher during wet season as compared to dry season in monocrop of coconut. The absorption was more from the surface layers during wet season and root explored deeper soil layers during dry season. Irrigation in general improved absorption of radiolabel in coconut. The uptake was more from the surface soil under irrigated conditions than that under rainfed conditions.
Seasonal influence on the grain yield of rice
(Kerala Agricultural University, Vellanikara, 2001) Beena, C; Balachandran, P V
Studies on the performance of four varieties of green gram (Phaseolus aureus Roxb.) under graded levels of phosphorus
(Department of Agronomy, College of Horticulture, Vellanikkara, 1979) Balachandran, P V; Sasidhar, V K
An experiment was conducted at the Instructional farm, attached to the College of Horticulture, Vellanikkara, during the period from June to September 1978 to study the performance of four varieties of green gram (Phaseolus aureus Roxb.) under graded levels of phosphorus.
Urease activity in rice soils as influenced by moisture regimes and rice rhizosphere
(Kerala Agricultural University, 1993) Saraswathi, P; Balachandran, P V
Urease activity in six rice soils of Kerala namely laterite (Oxisol), karappadam (Inceptisol), kari (Inceptisol), kole (Inceptisol) and black soil (Vertisol) were studied at 60% WHC and under submergence. The pattern of urea hydrolysis was same at 60% WHC and under submergence. While the black soil exhibited the highest urease activity, kari soil registered the lowest activity. When soils were incubated for periods longer than 5 h (at both the moisture regimes) the urea hydrolysis was complete within two days in laterite, karappadam and kayal soils. For black and kole soils it took five days and for kari soil 30 days for the completion of urea hydrolysis. The rice rhizosphere was found to have a positive influence on urease activity and the maximum urease activity in the rhizosphere was noticed at 60lh day after planting.
Urease activity in rice soils of Kerala
(Department of Agronomy, College of Horticulture, Vellanikkara, 1989) Saraswathi, P; Balachandran, P V
An investigation on the urease activity of rice soils of Kerala was conducted at the College of Horticulture, Vellanikkara during the period 1987-1989. Representative soil samples were collected from six rice soils of Kerala, namely , laterite karppadam, kari, kayal, kole and black soil . The kinetics of urease activitywas worked out employing Lineweaver-Burk equation of double reciprocal plot. The effect of different factors like pH, soil submergence and rice rhizosphere on soil urease activity was investigated . A comparision of the efficiency of the different methods of urease assay was also made. The radioassay and autoradiograph of the plants which were allowed to absorb 14 C - urea were also done.