• 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:
    • Zaidi, J. H.
    • Matiullah
    • Husaini, S. N.
    • Arif, M.
  • Source: Journal of Radioanalytical and Nuclear Chemistry
  • Volume: 290
  • Issue: 3
  • Year: 2011
  • Summary: Due to the inadequate water sources, usually sewerage water and industrial effluents are being use for irrigation of the agricultural land around the industrial areas in Pakistan wherein crops and vegetables are cultivated. As untreated effluents contain heavy elements, toxic metals and organic pollutants that may find its way through food chain to general public and may cause health hazards. It is, therefore, mandatory to assess the toxic metals in such crops and vegetables. In this regard, samples of corn, millet, cabbage, spinach and potato were collected within the vicinity of industrial areas of the Faisalabad and Gujranwala regions. The food samples were analyzed using neutron activation analysis (NAA) technique. The highest concentration values of Arsenic (1.90.1 g/g) and Cobalt (0.850.01 g/g) were found in cabbage whereas Manganese (91.60.2 g/g), Antimony (0.150.03 g/g) and Selenium (1.10.1 g/g) were observed in spinach and Chromium (9.631.3 g/g) was found in millet crop. The observed concentrations of all the toxic and heavy metals in crops and vegetables are higher than those reported in the literature.
  • Authors:
    • Grant, C.
    • Cai, D.
    • Wu, X.
    • Sun, Y.
    • Feng, Z.
    • Zhang, D.
    • Zhang, X.
    • Zhao, Q.
    • Meng, C.
    • Dai, K.
    • Yang, Y.
    • Wang, X.
    • Jia, S.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 90
  • Issue: 3
  • Year: 2011
  • Summary: A field micro-plot experiment for winter wheat was conducted in an irrigated winter wheat ( Triticum aestivum)-summer maize ( Zea mays L.) rotation system in Mazhuang, Xinji of Hebei province in the North China Plain, using the 15N isotope method to determine the effects of N application (rates and timing), and irrigation frequency on urea- 15N fate, residual-N and N recovery efficiency (NRE) of wheat. The experiment was conducted under two irrigation treatments (I2 and I3, representing for two and three irrigations, respectively), at three N rates (150, 210, and 270, kg ha -1), divided between two 15N-labeled applications of basal- 15N (90 kg ha -1) and topdress- 15N (60, 120, and 180, kg N ha -1, respectively). The total N uptake by wheat (ranging from 186 to 238 kg ha -1) and the fertilizer-derived N (Ndff, about 34-55%) were measured. The Ndff from labeled basal- 15N and from labeled topdress- 15N were about 15-22% and 16-40%, respectively. The NRE (measured either as recovery in grain or as the total N recovery in the plant) was higher with I3 (39-41 or 47-49%) than with I2 (35-40 or 42-47%), showing maximum NRE in grain of about 40% both at N210 with I2 and at N150 with I3 treatment. The NRE by the first wheat crop (in grain or the total N recovery in plant) was higher with labeled topdress- 15N (39-48 or 45-56%) as compared to that with labeled basal- 15N (30-37 or 36-45%), while the unaccounted N losses were lower with labeled basal- 15N (14-22%) relative to labeled topdress- 15N (14-35%). Higher residual N in soils was found with labeled basal- 15N (41-51%), as compared to labeled topdress- 15N (18-35%). Residual N in the 0- to 150-cm soil depth ranged from 26 to 44% while the unaccounted N losses ranged from 14 to 30%. Recovery of residual N by the 2nd and 3rd crops in the rotation was 5-10% in the maize crop and a further 1.7-3.5% in the subsequent wheat crop. The accumulated N recovery and the unaccounted N losses in continuous wheat-maize-wheat rotations derived from labeled topdress- 15N were 54-64% and 16-37%, respectively while they were 47-53% and 16-28%, respectively from labeled basal- 15N. This study also suggested that an N rate of 210 kg ha -1 (with a ratio of basal-N to topdress-N of 1:1.3) with two irrigation applications could optimize wheat grain yields and NRE, under the water limited conditions in North China Plain.
  • Authors:
    • Arpaia, M. L.
    • Sanden, B.
    • Kallsen, C. E.
  • Source: HortScience
  • Volume: 46
  • Issue: 8
  • Year: 2011
  • Summary: The objective of this study was to measure effects of late-season water stress on fruit yield, size, quality, and color of an early-maturing navel orange cultivar, Citrus sinensis (L.) Osbeck 'Beck-Earli'. Three irrigation regimes were initiated in August in the southern San Joaquin Valley of California in 2006, 2007, and 2008. Increasing levels of water stress resulted in decreasing midday shaded leaf water potential (SLWP) ranging from -1.4 MPa in early September to a minimum of -2.5 MPa at harvest. Generally, over the course of the 3 years, late-season water stress decreased fruit grade and increased soluble solids concentration (SSC), titratable acidity (TA), the BrimA index, and orange color. Fruit juiciness and SSC:TA ratios were unaffected by late-season water stress. The intensity of the water stress in 2007 decreased fruit yield by number and weight and decreased the percentage of large fruit. When trees exposed to 2 years of late-season water stress were fully irrigated the next year, fruit yield and quality were similar to trees that had not experienced late-season water stress for the 3 years of the study.
  • Authors:
    • Sharief, A. E.
    • Badawi, M. A.
    • Attia, A. N.
    • Kandil, A. A.
    • Abido, W. A. E.
  • Source: Journal of Applied Sciences Research
  • Volume: 7
  • Issue: March
  • Year: 2011
  • Summary: Two field experiments were conducted at the Experimental Station, Faculty of Agriculture, Mansoura University, Egypt during 2007 and 2008 seasons. The objectives of this investigation is aimed to study the effect of water tension treatments, organic and inorganic fertilizer combinations and their interactions on quality, storability and chemical analysis of potato Spunta cultivar. Each irrigation treatments were conducted in a separate experiment. Every separate experiment laid-out in randomized complete block design with four replicates. Results indicated that highest averages of tuber length and diameter, nitrogen content in foliage and protein content in tubers were recorded with irrigation at irrigation at 26cb (5360.17 m 3 water/ha) i.e. 54.1% from field capacity in both seasons. Application of 60% mineral nitrogen fertilizer (238 Kg N/ha) plus 40% organic chicken manure (158 Kg N/ha) produced the highest averages of tuber length, tuber diameter, nitrogen content in foliage and protein content in tubers in both seasons. Adding 80% mineral nitrogen fertilizer (317 Kg N/ha) plus 20% organic chicken manure (79 Kg N/ha) recorded the highest averages of dry matter content after storage in Newalla & refrigerator. Results indicated that irrigation at 34cb (3449.62 m 3 water/ha) i.e. 45.8% from field capacity and adding 20% mineral nitrogen fertilizer (79 Kg N/ha) plus 80% organic chicken manure (317 Kg N/ha) produced the maximum values of dry matter content. It could be accomplished that irrigation at 26cb (5360.17 m 3 water/ha) i.e. 54.1% from field capacity as well as application of 60% mineral nitrogen fertilizer (238 Kg N/ha) plus 40% organic chicken manure (158 Kg N/ha) maximized averages of tuber length, diameter, nitrogen content in plant foliage and protein content in tubers.
  • Authors:
    • Sharief, A. E.
    • Badawi, M. A.
    • Attia, A. N.
    • Kandil, A. A.
    • Abido, W. A. H.
  • Source: Australian Journal of Basic and Applied Sciences
  • Volume: 5
  • Issue: 9
  • Year: 2011
  • Summary: Water irrigation and reducing mineral nitrogen fertilizer are critical factors to regional development. The objectives was to study the effect of water tension treatments, mineral of nitrogen and organic fertilizers combinations and their interactions on yield and its components of potato. Each irrigation treatments were conducted in a separate experiment. Every separate experiment laid-out in randomized complete block design with four replicates then combined analysis was done between irrigation treatments. Irrigation at 26cb i.e. 54.1% moisture from field capacity produced maximum values of all studied traits, except unmarketable tuber yield, tuber less than 30 mm and water use efficiency, which resulted from irrigation at 34cb i.e. 45.8% moisture from field capacity. Application of 60% inorganic nitrogen (238 kg/ha)+40% organic chicken manure (158 kg N/ha) resulted in highest values of number of tubers/plant, total tuber yield/ha, marketable tuber yield/ha, tuber grades 30-60 mm (%), tuber grades more than 60 mm (%) and WUE (kg/m 3). The interaction between both studied factors had a significant effect on all studied character, with exception un-marketable tuber yield, tuber grades less than 30 mm and more than 60 mm (%). Highest WUE were obtained as a result of irrigation at 34cb i.e. 45.8% moisture from field capacity and using 100% N inorganic and or 60% inorganic nitrogen (238 kg N/ha)+40% organic chicken manure (158 kg N/ha). It could be concluded that highest averages of WUE was recorded with irrigation at 34cb and application of 100% inorganic fertilization and /or irrigation at 34cb and application of 60% inorganic nitrogen+40% organic chicken manure.
  • Authors:
    • Shaaban, S. H. A.
    • El-Fouly, M. M.
    • Khalifa, R. K. M.
    • Hamouda, H. A.
  • Source: Journal of American Science
  • Volume: 7
  • Issue: 5
  • Year: 2011
  • Summary: The present work aimed to determine the nutritional status of Balady mandarin orchards, through soil testing and leaf analysis, in order to work out a proper fertilization programs. A field study was conducted at El-Tall El-Kepeer, Ismailia governorate, covering 19 Balady mandarin orchards grown on sandy soils under drip irrigation. These soils are of poor fertility. However, fertilization of these orchards still depends upon the grower's inherited knowledge and in very small scale on the extension information. The trees were fifteen years old. The orchard soils had very high pH values, low to high level of EC and Na, and were low in total CaCO 3 and very low in O.M. The values for available nutrients in soil were found to be as very low of P, Fe, Mn, Zn and Cu. Values of K, Mg ranged between very low to medium levels, However values of Ca ranged between medium to high levels. The leaf macronutrient values were low in N, ranged between optimum to high in P and Mg, ranged between low to high in K, However values of Ca was ranged between low and optimum. The leaf micronutrient contents were as follow, Fe ranged from optimum to high; Mn, Zn and Cu were ranged from low to the beginning of optimum levels. The nutrient correlations of the leaves revealed some antagonisms between K and Ca, Mg and both of Mn and Zn. Also, the nutrient correlations of the leaves and fruits revealed some antagonisms between N in leaves and Zn in fruits, P and K in leaves and Mn in fruits, K in leaves and N, Cu in fruits, Ca in leaves and K in fruits.
  • 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.
  • Authors:
    • Kugbei, S.
  • Source: Journal of Crop Improvement
  • Volume: 25
  • Issue: 3
  • Year: 2011
  • Summary: Production figures in 2008 showed that new private seed enterprises in Afghanistan produced and sold about 12,000 tons of certified wheat seed, which accounted for 95% of the total certified seed produced in the country. At a retail price of about US$1,200 per ton, the enterprises earned an average margin of 20%. When interviewed, the farmers ranked high yield as by far the most important characteristic they sought in improved varieties. Besides yield, the next important attributes were earliness, disease resistance, grain color, and bread making quality. Estimates of on-farm productivity showed that use of improved wheat varieties alone could contribute up to 33% incremental yield under irrigated conditions, whereas the use of quality seed could enhance yield further by 28%. These estimates were obtained under recommended fertilizer rates, in the absence of which yield levels would have declined substantially. Apart from wheat, other major crops the farmers grew varied by regions but in broad terms included rice, vegetables, maize, potato, cotton, barley, watermelon, and alfalfa.
  • Authors:
    • Chachar, Q. I.
    • Shahzadi, A. K.
    • Mari, J. M.
  • Source: Journal of Agricultural Technology
  • Volume: 7
  • Issue: 1
  • Year: 2011
  • Summary: The study on perception of the problems in farming community in District Hyderabad, Pakistan was conducted through a set of questioners during 2007. Three hundred respondents (growers) were personally interviewed, their responses were tabulated. Data were collected on the basic information about cotton growers such as their ages, education, tenancy statuses, sizes of farm, farming experiences, and living status was asked which would highly influence the use of communication media for the perception of the problems in farming community. The growers of the area stated that irregular supply of irrigation and lack of visit of extension personnel, nonavailability of inputs, and high cost of inputs were common problems of the area. It was also noted that these are the causes for low yield. It is recommended that government should ensure the better facilities for continue supply of irrigation water and pure inputs with minimum rates in the market.