• Authors:
    • Hashimoto, A.
    • Ito, R.
    • Togami, T.
    • Kameoka, T.
  • Source: Agricultural Information Research
  • Volume: 20
  • Issue: 3
  • Year: 2011
  • Summary: In Nanki, Mie Prefecture, Japan, the mulching and drip irrigation system produces high-quality fruit despite large variations in the weather. For this cultivation system, we developed a small, stationary agricultural robot, "Field Server", which measures environmental and growing conditions in real time in the orchard. Our goals were to solve the problem of loss of the skills developed by experienced farmers due to a lack of new agricultural workers and aging of farmers, and to cultivate mandarin oranges with the required quality under occasionally severe and highly variable climate conditions. In this research, we demonstrated the ability of Field Server to monitor the agro-environmental conditions that affect plant physiology and the farmer's attitude towards their work and demonstrated the eKo wireless sensor network that was designed for agricultural use. To accomplish our goals, we installed a sensor network to support long-term, stable operation, including optimal placement of sensor nodes, optimal installation of the sensors and modification of network connections with Internet, and developed user-friendly Field Server and eKo data browsing software to help agricultural workers. Long-term data acquisition for a 1-ha agricultural site became possible due to improvements of the eKo system's hardware and software. In addition, the development of databases and related software permitted comparisons of the acquired data with data obtained from nearby AMeDAS stations. The comparison revealed the importance of agro-environmental monitoring (especially for rainfall) close to the production area and of soil moisture measurement to guide irrigation and produce high-quality mandarin oranges.
  • Authors:
    • Koc, D. L.
    • Tekin, S.
    • Kapur, B.
    • Kanber, R.
    • Unlu, M.
  • Source: African Journal of Biotechnology
  • Volume: 10
  • Issue: 12
  • Year: 2011
  • Summary: This study was carried out to determine the crop water stress index (CWSI) for drip irrigated cotton grown on a heavy clay texture soil ( Palexerollic Chromoxerert) under semi-arid climatic condition of East Mediterranean region for three years (2005 to 2007) in Adana, Turkey. Four irrigation treatments designated as full (I 100) with no water stress and slight (DI 70), moderate (DI 50) and strong water stress (continuous stress, dry land) (DI 00) were tested. The treatments of DI 70 and DI 50 received water amount of 70 and 50% of the control treatment and the DI 00 was not irrigated except for germination water given at the beginning of the growing season. Irrigation was initiated when leaf water potential (LWP) reached to -15 bar for full (I 100), -17 bar for DI 70 and -20 bar for DI 50 irrigation treatments. After first irrigation, all the treatments were irrigated at one week interval. The deficit irrigation affected, the irrigation water use, seed cotton yield, dry matter and some yield components such as plant height and number of boll per plant of cotton. Average values of water use, seed cotton yield, dry matter and water use efficiency of full irrigated cotton were 578 mm, 3.28 tha -1, 13.44 tha -1 and 0.59 kgm -3, respectively. CWSI values were calculated from the measurements of canopy temperatures by infrared thermometer (IRT), ambient air temperatures and vapor pressure deficit values for all the irrigated treatments. A non-water stressed baseline (lower baseline) equation for cotton was developed using canopy temperature measured from full irrigated plots as, T c - T a =-1.7543 VPD+1.56; R 2=0.5327 and the non-transpiring baseline (upper baseline) equation was built using canopy temperature data taken from continuous stress plots as, T c - T a =-0.0217 VPD+3.2191. The trends in CWSI values were consistent with the varying soil water content due to the deficit irrigation programs. The relationships between mean CWSI and plant parameters considered in this study were linear except for irrigation water amount. Both dry matter and seed cotton yield decreased with increased soil water deficit. Seed cotton yield (SY) and seasonal mean CWSI values relationship were obtained as, SY=-2.3552 CWSI+3.5657; R 2=0.499. This relationship can be used to predict the seed cotton yield. The results suggest that the cotton crop for this particular climate and soil conditions, should be irrigated when CWSI approaches 0.36. The CWSI approach, according to results of this study, can be accepted as a useful tool to schedule irrigations for cotton.
  • Authors:
    • Kapur, B.
    • Tekin, S.
    • Koc, D. L.
    • Kanber, R.
    • Unlu, M.
  • Source: Agricultural Water Management
  • Volume: 98
  • Issue: 4
  • Year: 2011
  • Summary: A field study on cotton ( Gossypium hirsutum L., cv.) was carried out from 2005 to 2008 in the Cukurova Region, Eastern Mediterranean, Turkey. Treatments were designated as I100 full irrigation; DI 70, DI 50 and DI 00 which received 70, 50, and 0% of the irrigation water amount applied in the I100 treatment. The irrigation water amount to be applied to the plots was calculated using cumulative pan evaporation that occurred during the irrigation intervals. The effect of water deficit or water stress on crop yield and some plant growth parameters such as yield response, water use efficiencies, dry matter yield (DM), leaf area index (LAI) as well as on lint quality components was evaluated. The average seasonal evapotranspiration ranged from 28715 (DI 00) to 58480 mm ( I100). Deficit irrigation significantly affected crop yield and all yield components considered in this study. The average seed cotton yield varied from 1369197 (DI 00) to 3397508 kg ha -1 ( I100). The average water use efficiency (WUE ET) ranged from 6.01.6 ( I100) to 4.80.9 kg ha -1 mm -1 (DI 00), while average irrigation water use efficiency (WUE I) was between 9.43.0 ( I100) and 14.44.8 kg ha -1 mm -1 (DI 50). Deficit irrigation increased the harvest index (HI) values from 0.260.054 ( I100) to 0.320.052 kg kg -1 (DI 50). Yield response factor (Ky) was determined to be 0.98 based on four-year average. Leaf area index (LAI) and dry matter yields (DM) increased with increasing water use. This study demonstrated that the full irrigated treatment ( I100) should be used for semiarid conditions with no water shortage. However, DI 70 treatment needs to be considered as a viable alternative for the development of reduced irrigation strategies in semiarid regions where irrigation water supplies are limited.
  • Authors:
    • Trethowan, R.
    • Moeller, C.
    • Carrillo-Garcia, A.
    • Verhulst, N.
    • Sayre, K. D.
    • Govaerts, B.
  • Source: Plant and Soil
  • Volume: 340
  • Issue: 1/2
  • Year: 2011
  • Summary: A field experiment was conducted under furrow irrigation on a Vertisol in arid northwestern Mexico, to evaluate sustainable production alternatives for irrigated wheat systems. Treatments included: tillage (conventionally tilled raised beds where new beds are formed after disc ploughing before planting [CTB] and permanent raised beds [PB]) and irrigation regimes (full and reduced). Physical and chemical soil quality was compared among treatments. PB improved soil structure and direct infiltration, increased topsoil K concentrations (0-5 cm; 1.6 cmol kg -1 in PB vs. 1.0-1.1 cmol kg -1 in CTB) and reduced Na concentrations (0-5 cm; 1.3-1.4 cmol kg -1 in PB vs. 1.9-2.2 cmol kg -1 in CTB) compared to CTB. Crop growth dynamics were studied throughout the season with an optical handheld NDVI sensor. Crop growth was initially slower in PB compared to CTB, but this was compensated by increased crop growth in the later stages of the crop cycle which influenced final yield, especially under reduced irrigation. These results were reflected in the final grain yield: in the third year after conversion to PB, no difference in grain yield was found between tillage systems under full irrigation. However, under reduced irrigation the improved soil quality with PB resulted in a 19% and 26% increment in bread and durum wheat grain yields, respectively. As projected climatic scenarios forecast higher evapotranspiration, less reliable rainfall and increased drought, our results indicate that PB could contribute to maintaining and increasing wheat yields in a sustainable way.
  • Authors:
    • Merwe, S. van der
    • Verreynne, S.
  • Source: SA Fruit Journal
  • Volume: 10
  • Issue: 2
  • Year: 2011
  • Summary: Sunburn is a major problem on early maturing mandarins such as 'Miho Wase' Satsuma. Currently, optimal irrigation during critical periods and shade nets are the only measures to reduce losses due to sunburn. Previous work using particle film technology (kaolin) on citrus to reduce sunburn was very effective, but the formulation used resulted in insect repercussions. The objective of the study was to determine if products such as Screen TM, Vapor Gard, Silicon and Raynox TM can reduce tree canopy temperature and thereby reduce sunburn on 'Miho Wase' Satsuma mandarins. All treatments were applied three times between December 2009 and January 2010. Screen TM reduced the sunburn incidence (fruit per tree) by 50%, possibly due to reductions in leaf temperature by 2.53C and fruit temperature by 1.73C, without a negative effect on fruit quality. Screen TM increased the sugar content of fruit. Vapor Gard increased fruit temperature, reduced the sugar content of the fruit, and increased sunburn incidence by 16%. Raynox TM, Silicon, and the combination of Screen TM and Vapor Gard had no effect on sunburn incidence.
  • Authors:
    • Lu, X.
    • Gong, J.
    • Hou, Z. A.
    • Cui, J.
    • Wang, H. J.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 9
  • Year: 2011
  • Summary: Method: The experiment selected the major local cotton varieties Biaoza A 1 and Xinluzao33 as test materials and designed different irrigation water quantity and nitrogen (N) fertilizer quantity. Objective: Dry matter accumulation and differences between varieties were analyzed. Result: Result indicated that the total dry matter accumulation showed the change pattern of "slow-fast-slow" in two cotton varieties during the whole growing stage. The total dry matter accumulation were increased with the increase of irrigation water quantity and nitrogen fertilizer quantity, the maximum increasing rates augmented, and fast rising periods were delayed. But over-irrigation would lead to decrease of the total dry matter accumulation. Conclusion: Biaoza A 1 was higher in dry matter accumulation than Xinluzao33 at different treatments; the difference was not significant between varieties between varieties in low irrigation, but significant in medium and high irrigation.
  • Authors:
    • Yan, J. H.
    • Shi, L. S.
    • Hou, Z. A.
    • Cui, J.
    • Wang, H. J.
    • Lu, X.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 10
  • Year: 2011
  • Summary: The field experiment was conducted to research the effects and differences of different quantity of water and nitrogen application on cotton yield in two cotton varieties. The results show that the yields of two cotton varieties were increased significantly with the increase of water and nitrogen, but reduced with excessive irrigation water, the maximum cotton yield were obtained with treatment N 2W 2 (N 2: 360 kg/hm 2; W2: 4500 m 3/hm 2). The cotton yield of Biaoza A 1 is significantly higher than that of Xinluzao33, there was no significant difference between in treatment N 1W 1 and N 1W 3, other treatments showed significant difference in cotton yield between the two varieties. These results suggested that the yield and water and fertilizer use efficiency can be enhanced evidently by adopting suitable measures of water and fertilize application based on different cotton varieties.
  • Authors:
    • Wang, H. L.
    • Niu, J. Y.
    • Lv, X. D.
    • Wang, R. Y.
  • Source: Acta Prataculturae Sinica
  • Volume: 20
  • Issue: 5
  • Year: 2011
  • Summary: The crop water requirement is one of the most important factors in farmland water circulation system, study the effects of climate warming on water requirement of major crops in irrigated oasis in Hexi corridor when 1-4degreesC temperature rise in the future scenarios. The results show that climate change will have great impact on water requirement of cotton and corn, followed by spring wheat, when the temperature rises 1-4degreesC during the growth period, cotton, water requirement of cotton will increase by 2.17%-12.66%, equivalent to 15.00-83.00 mm; corn will increase by 1.90%-11.49%, equivalent to 14.60-82.50 mm; wheat will be increase by 1.80%-10.03%, equivalent to 9.70-50.70 mm. There are certain regional differences which the impact of climate change on crop water requirements. When the temperature increases 1degreesC, the crop water requirement of Wuwei in arid regions slightly larger than Dunhuang in extreme arid region; When increases 2degreesC, the demand almost equivalent. Dunhuang is greater than the Wuwei if increased 3 and 4degreesC. According to the current planting planning in Hexi Oasis, the given temperature scenario will cause an additional water requirement of 0.11, 0.21, 0.37, 0.62 million m 3 for cotton, 0.16, 0.33, 0.56, 0.93 million m 3 for corn; and 0.14, 0.26, 0.45, 0.71 million m 3 for spring wheat. The total irrigation water increase 0.41, 0.80, 1.38, 2.25 billion m 3. Climate warming will make the situation of water shortage more severe.
  • Authors:
    • Liu, S. H.
    • Liu, S. P.
    • Hu, W.
    • Wan, S. Q.
    • Kang, Y. H.
    • Wang, R. S.
  • Source: Agricultural Water Management
  • Volume: 100
  • Issue: 1
  • Year: 2011
  • Summary: A 3-year experiment was conducted in an extremely dry and saline wasteland to investigate the effects of the drip irrigation on salt distributions and the growth of cotton under different irrigation regimes in Xinjiang, Northwest China. The experiment included five treatments in which the soil matric potential (SMP) at 20 cm depth was controlled at -5, -10, -15, -20, and -25 kPa after cotton was established. The results indicated that a favorable low salinity zone existed in the root zone throughout the growing season when the SMP threshold was controlled below -25 kPa. When the SMP value decreased, the electrical conductivity of the saturation paste extract (EC e) in the root zone after the growing season decreased as well. After the 3-year experiment, the seed-cotton yield had reached 84% of the average yield level for non-saline soil in the study region and the emergence rate was 78.1% when the SMP target value was controlled below -5 kPa. The average pH of the soil decreased slightly after 3 years of cultivation. The highest irrigation water use efficiency (IWUE) values were recorded when the SMP was around -20 kPa. After years of reclamation and utilization, the saline soil gradually changed to a moderately saline soil. The SMP of -5 kPa at a depth of 20 cm immediately under a drip emitter can be used as an indicator for cotton drip irrigation scheduling in saline areas in Xinjiang, Northwest China.
  • Authors:
    • Wu, Z. G.
    • Hudan,T.
    • Yi, P. F.
    • Zhang, J.Z.
    • Wang, Y. M.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 47
  • Issue: 9
  • Year: 2011
  • Summary: Objective: This paper studied the effect of irrigation quota and application cycle on the growth of the cotton and its yield under the condition of mulched drip irrigation. Method: Different irrigation quota and cycles were designed. The soil moisture was monitored before and after the irrigation. The physiological index such as the budding amount and cotton height were measured at different stages of cotton growth. Result: The study shows that cotton's height is unsusceptible to the irrigation cycle in a state of low irrigation quota. With the irrigation quota increasing, the cotton's height is higher and higher; when the irrigation quota is certain, with the irrigation cycle increasing, the cotton's height is decreasing. When the irrigation quota is 3300 m 3/hm 2 and the irrigation cycle is 8d, the number of the bolls are the most, it is helpful for improving the cotton's production; when the irrigation cycle is 10d, the bolls are the fewest. Conclusion: When the irrigation quota is 5100 m 3/hm 2 and the irrigation cycle is 10d, it's helpful for the cotton's buds to appear early. When the irrigation quota is 4688 m 3/hm 2 and the irrigation cycle is 8d, the production is the highest and the comprehensive benefits is the most.