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Volume 1 Number 6 December 2015

Correction Equations for Wet Combustion Carbon Determination at Different Depths and Management Systems of a Rhodic Hapludox


Authors: Ademir De Oliveira Ferreira ; Jo?o Carlos Moraes S? ; Josiane Burkner Dos Santos ; Clever Briedis ; Thiago Massao Inagaki
Pages: 75-82
Abstract
Measurement of soil carbon is the focus of attention of present and future international conventions and agreements, related to global climate change. Past inventories and current carbon stock inventories involve different analytical methods, and methodological biases and uncertainties should be reduced to develop reliable estimates of the effects of land uses changes on total organic carbon. Furthermore, the carbon-equivalent is highly variable, and there is the need of using a specific correction factor for each location, resulting from the combination of land use, textural gradients, and sampling depth. In this context, the aims of this study were creating correction equations for the determinations through wet combustion (Walkley-Black- WB) for a Rhodic Hapludox based on the determinations made through dry combustion (CS) at different depths and management systems.  The experimental design was 4 x 5 factorial with 3 replications. Treatments were: Conventional Tillage (CT); Minimum Tillage (MT); No-till with chisel plowing (NTC) and No-Till (NT). The collection depths were: 0-2.5; 2.5-5; 5-10; 10-20 and 20-40 cm. The measured carbon equivalent values ranged from 1.06 to 1.18 and were dependent on land use and soil depth. Rhodic Hapludox under different management presented the following order of carbon equivalent values: NTC < CT < NT < MT. The carbon equivalent values increased with depth. The high ratio between C-WB and C-CS (R2= 0.75, p= 0.0001) justifies the use of correction factors.

Performance Evaluation of Tomato (Solanum Lycopersicum L.) Hybrids for Increased Productivity under Polyhouse Conditions in Temperate Areas


Authors: Vinod K Sharma ; Tribhuwan Singh
Pages: 68-74
Abstract
Tomato (Solanum lycopersicum L.) is one of the leading vegetable crops in the world. In order to harness boom in tomato productivity, tomato hybrids are evaluated under varied agro-climatic conditions especially protected conditions. In the present study, morphological and biochemical properties of fourteen fresh tomato hybrids were analyzed under polyhouse in mid hill condition of Uttarakhand, India. The experiment was conducted during s rainy eason of 2012-2013 in randomized block design with three replications and fourteen treatments (each hybrid representing one treatment). The results showed that the tomato hybrid Himraja could perform outstandingly well  for  various morphological and quality characters viz., plant height (315.00 cm), percent fruit set  (84.09 %), higher number of marketable fruits per plant (58.53), maximum marketable fruit yield per hectare (1080.00 q) and high TSS (7.98 ºBrix) as compared to all other hybrids. Besides, it also proved the best with respect to disease resistance and profitability.