• Authors:
    • Eryigit,T.
  • Source: Yuzuncu Yil Universitesi Journal of Agricultural Sciences
  • Volume: 21
  • Issue: 1
  • Year: 2011
  • Summary: The industrial crops with contribution to national income and industrial sector in terms of providing raw materials have a significant place in our crop production. Agricultural industry in our country has a large capacity, but due to lack of raw materials and financing a significant portion of the installed capacity can not be benefited. Especially in recent years, increasing of population and production decrease in some industrial plants due to the resulting vegetable oil deficit. Our country pays the highest foreign currency to imports of the oil and oil seed crops for closure of this gap after the oil imports. Therefore, the priority should be given to the oil plants within the groups of industrial plants. Igdr has its own microclimate characteristics. The diversity of product design is greater due to the climate and irrigation conditions in the plain. Grains constitute the main products of the region. All kinds of vegetables, olives and citrus fruit except that all the fruits can be grown. Sugar beet and cotton plants of industrial crop and the alfalfa plants of the forage crops have great importance in the development of animal husbandry. However, in recent years, changes in the climate regime, increases in the cultivation of sugar beet, sunflower and rapeseed gave rise to a decrease in the number of the small farmers who planted cotton. Igdr has high agricultural potential, so the alternative species of industrial crops and their varieties will be integrated to the present cultivation of plain by the scientific studies which will be held on industrial crops in the province.
  • Authors:
    • Virendra, K.
    • Gorantiwar, S. D.
    • Gadge, S. B.
    • Mahesh, K.
  • Source: Journal of Agrometeorology
  • Volume: 13
  • Issue: 1
  • Year: 2011
  • Summary: A study was carried out to estimate crop evapotranspiration (ETc) for different crops growing under surface (SI) and microirrigation (MI) methods in the command area of Mula Irrigation Project in Maharashtra, India. A spreadsheet-based computer model was developed to estimate the ETc values and compute the water requirement. The climatological data obtained from the meteorological observatory located at All India Co-ordinated Research Project on Water Management, Rahuri (Maharashtra), from 1975 to 2005 was used. The crop water requirement under MI methods was less than that under SI methods. The saving in water for MI method was maximum under pomegranate and lime (88%) and minimum for summer groundnut (38%) when compared to the SI method. Similar saving in water was also observed for other crops under MI methods. The percentage saving in MI methods was 75, 62, 64, 73, 68, 61, 43, 51, 65, 48, 53, 70, 63, 65, 63, 40, 52 and 63% for pawpaw, banana, sugarcane, grapes, kharif soyabean, rabi tomato, kharif groundnut, rabi onion, cotton, gram, potato, kharif brinjal [aubergine], cabbage, summer brinjal, summer cucumber, summer onion, summer okra and summer chilli, respectively, when compared to the water requirement under SI method. Thus, there is a saving of at least 50% of water if drip irrigation method is used instead of SI method. This indicates that in the case of water scarcity there is possibility of bringing additional area under irrigation by using the saved amount of water.
  • Authors:
    • Nagler, P. L.
    • Hunsaker, D. J.
    • Neale, C. M. U.
    • Glenn, E. P.
  • Source: Hydrological Processes
  • Volume: 25
  • Issue: 26
  • Year: 2011
  • Summary: Crop coefficients were developed to determine crop water needs based on the evapotranspiration (ET) of a reference crop under a given set of meteorological conditions. Starting in the 1980s, crop coefficients developed through lysimeter studies or set by expert opinion began to be supplemented by remotely sensed vegetation indices (VI) that measured the actual status of the crop on a field-by-field basis. VIs measure the density of green foliage based on the reflectance of visible and near infrared (NIR) light from the canopy, and are highly correlated with plant physiological processes that depend on light absorption by a canopy such as ET and photosynthesis. Reflectance-based crop coefficients have now been developed for numerous individual crops, including corn, wheat, alfalfa, cotton, potato, sugar beet, vegetables, grapes and orchard crops. Other research has shown that VIs can be used to predict ET over fields of mixed crops, allowing them to be used to monitor ET over entire irrigation districts. VI-based crop coefficients can help reduce agricultural water use by matching irrigation rates to the actual water needs of a crop as it grows instead of to a modeled crop growing under optimal conditions. Recently, the concept has been applied to natural ecosystems at the local, regional and continental scales of measurement, using time-series satellite data from the MODIS sensors on the Terra satellite. VIs or other visible-NIR band algorithms are combined with meteorological data to predict ET in numerous biome types, from deserts, to arctic tundra, to tropical rainforests. These methods often closely match ET measured on the ground at the global FluxNet array of eddy covariance moisture and carbon flux towers. The primary advantage of VI methods for estimating ET is that transpiration is closely related to radiation absorbed by the plant canopy, which is closely related to VIs. The primary disadvantage is that they cannot capture stress effects or soil evaporation. Copyright (C) 2011 John Wiley & Sons, Ltd.
  • Authors:
    • Lu, X.
    • Hou, Z. A,
    • Wang, H. J.
    • Xie, H. X.
    • Li, J.
    • Gong, J.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 10
  • Year: 2011
  • Summary: Objective: Effect of water, nitrogen and density coupling on the growth of hybrid cotton under film drip irrigation were studied. Method: A field experiment was carried out to study the growth and output of cotton treated by 8 test schemes of different water, nitrogen and density. Result: The results showed that the effect of water quantity on cotton yield was the most significant, the next was nitrogen and density. The yield of cotton was increased along with increasing of water and nitrogen quantity followed by nitrogen quantity and planting density. Conclusion: These results suggested that water and nitrogen in field farming should be used cautiously.
  • Authors:
    • Leib, B. G.
    • Gwathmey, C. O.
    • Main, C. L.
  • Source: Journal of Cotton Science
  • Volume: 15
  • Issue: 1
  • Year: 2011
  • Summary: Cotton ( Gossypium hirsutum L.) responses to supplemental irrigation need to be reassessed in humid, short-season environments. We conducted a 4-year study on a Typic Hapludalf at Jackson TN, to measure yield and maturity responses of contemporary cultivars to supplemental irrigation; to describe boll retention and distribution patterns associated with maturity responses; and to estimate the percentage of years in which yields may respond to irrigation. Treatments consisted of three rates of supplemental drip irrigation (nominally 3.81, 2.54, and 1.27 cm wk -1, adjusted for rainfall and prior irrigation), plus a non-irrigated check. Irrigation increased lint yields significantly in 3 of 4 years, with quadratic rate responses. The average yield increase was 38% at the 2.54-cm wk -1 rate. Yields were maximized with 35 to 37 cm of total water (irrigation+rainfall) between 40 and 120 days after planting. Yields were limited more by the accumulation of heat units than water supply in 2009. Irrigation delayed crop maturity by an average of 0.56 days for every additional cm water from irrigation or rainfall. Full irrigation expanded the effective fruiting zone on the plant from about 6.6 to 8.5 sympodial branches, increasing first position boll retention, but it delayed crop maturity mainly by shifting the location of the highest harvestable boll. Response to water supply showed that a yield response to irrigation could be expected in years with
  • Authors:
    • Xu, Y. L.
    • Gao, S.
    • Wang, J. C.
    • Han, X. F.
  • Source: Journal of China Agricultural University
  • Volume: 16
  • Issue: 3
  • Year: 2011
  • Summary: To explore the effect of under-mulch-drip irrigation on canopy photosynthesis, canopy structure and yield formation of hybrid cotton planted in Xinjiang, an experiment with limited drip irrigation was carried out under field condition. The results were as follow: limited drip irrigation caused water deficiency in cotton field, reduced canopy apparent photosynthesis (CAP) and leaf area index (LAI); under this treatment, the canopy respiration rates (CR) and the ratio of CR to total CAP were higher in fully flowering stage but fell rapidly in full boll stage. The limited drip irrigation increased leaf mean foliage inclination angle (MFLA), transmission coefficient for diffuse penetration (TCDP) and transmission coefficient for radiation penetration (TCRP), with low light interception rate; On the other hand, excessive drip irrigation promoted the over-rapid growth of hybrid cotton, canopy leaf source capacity (CLSC) and high dry matter accumulation. But CR increased rapidly at late growth stage, and CAP was at its minimum level, result in low yield. In the case of hybrid cotton, under appropriate irrigation treatment, CAP was higher, and LAI increased sharply. It maintained at a higher LAI level at late stage, so it had a steady growth and optimal leaf physiological function which led to higher yield. Studies showed that the suitable amount of drip irrigation for Zhaofeng-1 in South Xinjiang was 3 000-4 125 m 3/nm 2. Its corresponding yield was 7 714.3-8 289.5 kg/hm 2. The ideal canopy photosynthesis characteristic and canopy structure targets of hybrid cotton were discussed.
  • Authors:
    • Hebbar, K. B.
    • Mayee, C. D.
  • Source: Current Science
  • Volume: 100
  • Issue: 11
  • Year: 2011
  • Summary: There are several reasons why plants wilt. Some of them are over-watering, lack of water, too much sun, not enough sun, too many/much fertilizers, diseases caused by infection, etc. Wilt due to lack of water or other environmental factors generally occurs gradually and hence, the cause of those can be studied and accordingly it can be controlled by devising appropriate management strategies. Moreover, plants recover with appropriate control measures and continue to yield. In this review, we discuss a typical wilt which is sudden and occurs within a few hours. Hence, understanding the cause and devising a control measure are difficult. Its sporadic distribution and untimely occurrence further complicate the effort to find the cause of this wilt. Unlike the wilt mentioned above which occurs due to lack of water, sudden wilt occurs when the soil is suddenly saturated by a downpour of rain and the sun later shines bright and hot. Paradoxically, the physiological responses, i.e. wilt symptoms to those induced by either drought or flooding are similar. However, the causal mechanism is different. Here, we demonstrate that the imbalance in uptake and loss of water under flooding is the cause of sudden/parawilt of cotton. We also discuss how plants with rapid growth rate and climate factors like bright sunshine and high temperature accentuate the problem of parawilt in cotton.
  • Authors:
    • Lu, X.
    • Xie, X.
    • Wang, H. J.
    • Ye, J.
    • Hou, Z. A.
    • Hou, S.
  • Volume: 47
  • Issue: 9
  • Year: 2011
  • Summary: A field experiment was conducted to study cotton growth and nitrogen uptake in response to different water and nitrogen application rates under drip irrigation with saline water. Three irrigation water salinity levels were set as 0.35 (S 1), 4.61 (S 2) and 8.04 (S 3) dS/m; two water and nitrogen application rates were set as 405 (L 1), 540 (L 2) mm and 240 (N 1), 360 (N 2) kg/hm 2, respectively. The results showed that plant height of cotton were influenced significantly by water salinity, application rates of water and interaction between them, and the interaction among water salinity, water application rate and nitrogen application rate at earlier growth stage, but mainly affected by water application rate at the later stage. The order of plant height were S 2 > S 1 > S 3 with water application 540 mm (L 2), while no significant difference were found on the growth of plant height between two nitrogen rates. The dry matter accumulation of the cotton stem and leaves are influenced significantly by the interaction among water salinity, application rates of water and nitrogen application, but cotton bolls and total dry matter accumulation are not significantly influenced by the interaction. Nitrogen uptake of cotton was influenced significantly by water salinity, application rates of water and nitrogen, and interactions between two of them or among the three factors. Total nitrogen content of cotton reduced with water salinity increasing, but increased evidently when water application rate was increased. Those results suggest that higher water application rate can enhance nitrogen uptake of cotton under drip irrigation with saline water.
  • Authors:
    • Jansirani, R.
  • Source: Journal of Cotton Research and Development
  • Volume: 25
  • Issue: 2
  • Year: 2011
  • Summary: The study was conducted at Kovilpatti block of Tuticorin district of Tamil Nadu with the specific objective of studying extent of adoption of production technologies in Bt cotton by the growers. The area was selected based on the major cultivation of Bt areas and production of Bt cotton under irrigated condition. The selected respondents for this study were 90, who have adopted Bt cotton and non Bt cotton i.e 45 growers in each category by using simple random sampling method. The collected data were analyzed using percentage analysis. All the growers adopted Bt varieties and 95.55 per cent of the growers adopted appropriate time of planting. About 80.00 per cent of the growers adopted spacing. Three fourths (77.77%) of the growers adopted regular plucking intervals during harvest and 75.55 per cent of the growers adopted proper irrigation management followed by pest and diseases management (73.33%). More than fifty (66.66%) of the growers adopted preparation of fields to required tilth and formation of trenches followed by manures and fertilizers (62.22%) and number of split doses (57.77%). Out of ten technologies nine technologies were adopted more than fifty per cent by the growers due to the reasons that private firms have agreed to buy the produce from the farmers offering a minimum support prices. State Department of Agriculture has also introduced contract farming to assure remunerative prices to farmers.
  • Authors:
    • Shakir, A. S.
    • Rehman, H. U.
    • Sharif, M. B.
    • Hameed, A.
    • Qazi, A. U.
    • Khan, N. M.
    • Afzal, M.
  • Source: Pakistan Journal of Science
  • Volume: 63
  • Issue: 3
  • Year: 2011
  • Summary: Global demands for food & fiber are increasing, necessitating efficient management of the irrigated water. Vast-uncultivated but otherwise fertile lands in Baluchistan, Pakistan attract the authorities to develop the land for agriculture through irrigation. Kachhi plains are one of such areas that will be provided canal water through a gravity canal system off-taking from Indus river at Taunsa Barrage. Efficient use of water especially in arid climates requires good estimates of crop water requirements (CWR). Physical based methods of estimating crop water requirement including the Radiation-Resistance based methods take into account the energy radiated from various sources and the atmospheric resistance depending on air circulation and humidity. This study employs a radiation-resistance based Penman Monteith Equation (Allen et al., 1998) through a spread sheet based tool and CROPWAT software to estimate the crop water requirements in Kachhi Plains, the study area. The study compares the reference crop evapotranspiration with four other well known methods. Meteorological data namely rainfall, temperature, humidity, actual sunshine hours of the closest meteorological station i.e. Jacobabad station is used for the study. Crop coefficients are calculated using FAO guidelines. Total water requirement for Wheat is estimated as 380 mm, while that for Cotton is 928 mm. Crop water requirement calculated by the spreadsheet matches well with that from CROPWAT. The result differs by 3% from the crop water requirements estimated/used by the feasibility report of the Kachhi Canal. Staggering of major crops (wheat, cotton) have been incorporated while computing the CWR. The study can be used for optimization of the cropping pattern and can further be extended by estimation of crop water requirement using lysimeter in the study area. It can also be used to study the impact analysis of meteorological data on the crop water requirement.