Alternate Furrow Irrigation: A Practical Way to Improve Grape Quality and Water Use Efficiency in Arid Northwest China

Field experiments were conducted for two years to investigate the benefits of alternate furrow irrigation on fruit yield, quality and water use efficiency of grape (Vitis vinifera L. cv. Rizamat) in the arid region of Northwest China. Two irrigation treatments were included, i.e., conventional furrow irrigation (CFI, two root-zones were simultaneously irrigated during the consecutive irrigation) and alternate partial root-zone furrow irrigation (AFI, two root-zones were alternatively irrigated during the consecutive irrigation). Results indicate that AFI maintained similar photosynthetic rate (Pn ) but with a reduced transpiration rate when compared to CFI. As a consequence, AFI improved water use efficiency based on evapotranspiration (WUE ET , fruit yield over water consumed) and irrigation (WUE I , fruit yield over water irrigated) by 30.0 and 34.5%, respectively in 2005, and by 12.7 and 17.7%, respectively in 2006. AFI also increased the edible percentage of berry by 2.91-4.79% significantly in both years. Vitamin C (Vc ) content content of berry was increased by 25.6-37.5%, and tritrated acidity (TA) was reduced by 9.5-18.1% in AFI. This resulted in an increased total soluble solid content (TSS) to TA ratio (TSS/TA) by 11.5-16.7% when compared to CFI in both years. Our results indicate that alternate furrow irrigation is a practical way to improve grape fruit quality and water use efficiency for irrigated crops in arid areas.     

Reduction in Activity/Gene Expression of Anthocyanin Degradation Enzymes in Lychee Pericarp is Responsible for the Color Protection of the Fruit by Heat and Acid Treatment

Heat and acid treatments were reported to be a promising substitute for SO₂ fumigation in color protection of postharvest lychee （Litchi chinensis Sonn.） fruits, but the mechanism was not clear. In the present study, hot water （70°C） dipping followed by immersion in 2% HCl （heat-acid） substantially protected the red color of the fruit during storage at 25°C and inhibited anthocyanin degradation while hot water dipping alone （heat） led to rapidly browning and about 90% loss in anthocyanin content. The pH values in the pericarp of the heat-acid treated fruit dropped to 3.2, while the values maintained around 5.0 in the heat-treated and control fruit. No significantly different pH values were detected among the arils of heat-acid, heat treated and control fruit. Heat-acid treatment dramatically reduced the activities of anthocyanin degradation enzyme （ADE）, peroxidase （POD） and polyphenol oxidase in the pericarp. A marked reduction in LcPOD gene expression was also detected in heat-acid treated fruit, in contrast, induction was found in heat treated fruit. The pericarp of heat-acid treated fruit exhibited significantly lower respiration rate but faster water loss than that of the untreated or heat treated fruit. Taken together, heat treatment triggered quick browning and anthocyanin loss in lychee fruit, while heat-acid treatment protected the fruit color by a great reduction in the activities/gene expression of anthocyanin degradation enzymes and acidification of lychee perica.     

Evaluation of an ＂Attract and Kill＂ System to Combat Ceratitis capitata on Peach Trees in Tunisia

Attract and kill （AK） technology was evaluated against the Mediterranean fruit fly （Med-fly）, Ceratitis capitata W.. Treatment was carried out in two peach orchards of four hectares each; first one located in Borj-Touil and the second in El-Kssibi Mornag, Northern Tunisia during the 2012 field season. AK is a specialized system based on hydrolyzed proteins and alpha-cypermethrin. During this study, 400 AK bait stations were placed in every hectare, four weeks before fruits color changes. The tested AK system was found effective in reducing the number of C. capitata population to 70% comparing to the untreated orchards. Fruit damages assessment showed significant differences between treatments in respect of decreasing infestation onto fruits Study results indicated that AK baited treatments were able to reduce dropped and soften fruits infestation seven times than that of control plots. Fruit damages were restricted to 4%-5% in treated areas with AK system in compare to 31%-35% recorded in control plots. This novel AK system showed good performance to combat Med-fly and can successfully used to combat various fruit fly species when applied for an area wide application program.     

Dynamic Changes in the Calcium Content of Several Apple Cultivars During the Growing Season

Dynamic changes in calcium content were investigated in eight apple cultivars. The results showed that the calcium concentration in leaves and shoots increased with fruit development. The cultivars displayed only a small difference in the calcium concentration during the early stage of development, the difference became very significant at the late stage of development, especially in shoots. In shoots, for example, calcium content was highest in Starkrimson （19 638.6 mg kg^-1） and lowest in Fuji （8 751.3 mg kg^-1）. Calcium concentration was highest in young fruits and was found to decrease with the growth of fruit, and was characterized by a dramatic drop at the rapid expansion stage. There was a significant difference among cultivars. Young Starkrimson fruits contained the highest calcium concentration of 506.52 mg kg^-1 among cultivars tested, followed by Pink Lady and Fuji. The calcium concentration in mature fruits from high to low is as follows： Starkrimson, Sansa, Pink Lady, Senshu, Gala, Fuji, Red General and New Century. In this study, it was found that eight cultivars continuously assimilated calcium during the whole growing season, especially at the young stage when fruit took up 35-46% of total calcium. The calcium content in fruitlets was low in all cultivars; in the expansion stage, there was rapid absorption of about 30% of total calcium, whereas in the ripening fruit, content of calcium was reduced. The calcium accumulation increased with fruit growth in stalk, similar to that in fruit.     

Study on the Resistance Induced by Salicylic Acid Against Phytophthora capsici in Pepper （Capsicum annuum）

Pepper Phytophthora blight caused by Phytophthora capsici L. is the most destructive disease for reducing pepper yields in the world. Building up varietal resistance and induced resistance to the disease are of agricultural importance. In this paper, the disease resistance induced by salicylic acid (SA) against P. capsici were studied by using four hot pepper lines with different resistant abilities and one P. capsici strain with middle pathogenicity. Results show that SA could induce significantly the resistance of pepper seedlings to P. capsici, but CaCl2, KH2PO4 and VAM couldn‘t. SA at a relative low concentration from 0, 15 to 0.3 g L^-1 had no antifungal activity in vitro against P. capsici, That means the disease resistant enhancement of the plants treated with SA is due to the induction effect, but not the antifungal effect of SA. About 1 to 5 days internal between SA-treatment and challenge inoculation was sufficient to induce the disease resistance of hot pepper. The resistance could remain more than 20 days after treatment with SA.     

Changes of the Main Carotenoid Pigment Contents During the Drying Processes of the Different Harvest Stage Fruits of Lycium barbarum L

The test analyzed the regularity of biosynthesis and degradation of the main functional components, such as zeaxanthin, β-carotene, and esterified carotenoids in the fruit of Lycium barbarum L. in order to provide theoretical basis for improvement of processing condition, appearance quality, and preservation of carotenoids. RP-HPLC was adapted to assay the changes of the main carotenoids of the different harvested stage fruit during the drying processing. Quantification was realized using external standard with gradient elution. The results showed that zeaxanthin and β-carotene contents in fruits increased dramatically, 2-22 times that of fresh fruits at the beginning of the drying period. In the middle of drying period, degradation occurred to a some extent, and the fall fruit degraded to a large extent. At the end of drying period, zeaxanthin and β-carotene contents increased to a little extent until a balanced state is obtained. Zeaxanthin dipalmitate content had a total degradation to more than 40% at the beginning of the drying period, and increased a little at the middle period, then reached a balanced state finally. The total carotenoid content analysis showed that the summer fruit had higher carotenoid content than the fall fruit. The experiments demonstrated zeaxanthin and β-carotene contents in fruits increased and zeaxanthin dipalmitate decreased during the drying process, which had an effect on the production appearance.     

Reduction of Chilling Injury and Ultrastructural Damage in Cherry Tomato Fruits After Hot Water Treatment

The effects of hot water treatment in alleviating chilling injury and reducing ultrastructural damage of mature-green cherry tomatoes （Lycopersicun esculentum cv. cerasiform Alef） were investigated. Mature-green cherry tomato fruits were treated in water at 40℃ or 45℃ for 5 min or 15 min, and then stored at 5℃ for 19 days followed by ripening at 20℃. Water treatment at 40℃ for 15 min increased tolerance of cherry tomato fruits to chilling stress, indicating as low outbreak of skin lesion, high color a＊ value, and low electrolyte leakage. Treated fruits showed typical climacteric respiration and developed normal red color with chlorophyll degradation and lycopene accumulation during ripening, while fruits without treatment failed to develop red color and suffered skin lesion. After 19 days of chilling, heated fruits showed the conversion of chloroplast to chromoplast with the disappearance of thylakoids. Mitochondria and other cell organelles were not adversely affected in treated fruits. However, ultrastructures in pericarp cells in control fruits severely damaged with extensive disorganization of cytoplasm, swelled chloroplasts, distorted and unstacked thylakoids. Chloroplast was the first and most severely impacted organelle by chilling stress. Hot water treatment （40℃ for 15 min） before storage alleviated chilling injury in cherry tomato fruits. The results suggest that chilling injury is related with the damage of cell structure under chilling stress.     

Effects of Nitric Oxide and Exogenous Ethylene Treatments on Ethylene Biosynthesis in Feicheng Peach

The effects of nitric oxide （NO） and exogenous ethylene on ethylene biosynthesis in harvested Feicheng peaches were studied. The antagonistic actions between NO and exogenous ethylene was also investigated. The Feicheng peaches were fumigated with 10μL L^-1 NO, 1 000 μL L^-1 ethylene, or 10 μL L^-1 NO plus 1 000 μL L^-1 ethylene for 3 h. The results suggested that application of exogenous ethylene promoted the biosynthesis of endogenous ethylene in peach fruit. The treatment with NO remarkably inhibited the biosynthesis of ethylene by significantly reducing the activities of ACC synthase （ACS） and ACC oxidase （ACO）. Ethylene biosynthesis in the fruits treated with both NO and exogenous ethylene was lower than that in fruits treated with exogenous ethylene alone but higher than that in fruits treated with NO alone, suggesting that there were antagonistic actions between NO and exogenous ethylene. NO could inhibit the biosynthesis of ethylene and the catalysis of exogenous ethylene during ethylene biosynthesis in peach fruits.     

What are the differences in yield formation among two cucumber (Cucumis sativus L.) cultivars and their F1 hybrid?

To elucidate the mechanisms underlying the differences in yield formation among two parents(P1 and P2) and their F1 hybrid of cucumber, biomass production and whole source–sink dynamics were analyzed using a functional–structural plant model(FSPM) that simulates both the number and size of individual organs. Observations of plant development and organ biomass were recorded throughout the growth periods of the plants. The GreenLab Model was used to analyze the differences in fruit setting, organ expansion, biomass production and biomass allocation. The source–sink parameters were estimated from the experimental measurements. Moreover, a particle swarm optimization algorithm(PSO) was applied to analyze whether the fruit setting is related to the source–sink ratio. The results showed that the internal source–sink ratio increased in the vegetative stage and reached a peak until the first fruit setting. The high yield of hybrid F1 is the compound result of both fruit setting and the internal source–sink ratio. The optimization results also revealed that the incremental changes in fruit weight result from the increases in sink strength and proportion of plant biomass allocation for fruits. The model-aided analysis revealed that heterosis is a result of a delicate compromise between fruit setting and fruit sink strength. The organlevel model may provide a computational approach to define the target of breeding by combination with a genetic model.     

Regulation of Propylene and 1-Methylcyclopropene on Expressions of ACS and ACO Genes in Persimmon Fruits

The regulation of postharvest treatment with propylene and 1-MCP on ethylene release rate and expressions of 1- aminocyclopropane-l-carboxylic acid synthase （ACS） and 1-aminocyclopropane-1-carboxylic acid oxidase （ACO） genes in Fuping Janshi persimmon （Diospyros kaki L.） fruit were investigated. Fruits were treated with propylene and 1-MCP, then stored at 20℃, ethylene release rate of the treated fruits was measured at regular intervals and RNA was extracted for Northern blotting analysis. The results suggested that treatment with propylene accelerated the expressions of ACS and ACO genes and then enhanced the ethylene biosynthesis, while treatment with 1-MCP inhibited the expressions of two genes and their ethylene biosynthesis. Furthermore, different effects on expressions caused by treatments with propylene and 1-MCP existed in various fruit tissues, the inhibitory effect on ACS and ACO genes by 1-MCP was the strongest in pericarp, followed by pulp and core tissues, in the area near fruit stalk, the inhibitory effect was the weakest. While the enhanced effect on ACS and ACO genes by propylene increased from pulp, core, and pericarp to the area near fruit stalk. Expression of each member of ACS and ACO families in various tissues was also completely different, in control and propylene treatment, DKACS3 gene just expressed in the area near fruit stalk and did not express in other tissues, but DKACS2 gene expressed in four tissues by treatment with propylene.     

Effects of Subsoiling on Soil Moisture Under No-Tillage for Two Years

In order to improve the water use efficiency under conservation tillage, the effects of subsoiling on soil moisture under notillage were studied. An experiment of 40 cm subsoiling in a field kept under no-tillage for 2 years was operated from 2005 to 2006. Based on the data of the soil moisture and crop yield, the physical basis of subsoiling for water conservation and yield increase was analyzed. The results showed that the soil water storage under subsoiling, from the soil surface to a depth of 100 cm was more than that under no-tillage for the growth season. In the 0-100 cm soil depth, the soil moisture in 50-100 cm depth under subsoiling was more compared with no-tillage, which increased when it＇s drought and decreased when it＇s rainy with the increase in soil depth. Compared with no-tillage, subsoiling could reduce the water consumption of oats in the 0-50 cm depth and increase the water consumption in the 50-100 cm depth. Also, subsoiling increased the yield by 18.29% and the water use efficiency by 16.8% in a two-year average. The effects of subsoiling on water conservation and yield increase were affected by precipitation, and a well-proportioned rainfall was better to increase yield and water use efficiency. Meanwhile, subsoiling decreased bulk density, which increased with the available precipitation. Subsoiling under no-tillage is the effective rotation tillage to contain more soil moisture and improve water use efficiency in ecotone of North China.     

Efficacy of Ceranock Attract and Kill System as a Control Method of Mediterranean Fruit Fly, Ceratitis capitata in Apricot Orchards in Central Iraq

A field experiment was conducted using Ceranock bait station, ＂attract and kill＂ system to combat Mediterranean fruit fly, Ceratitis capitata, in apricot orchards, Central of lraq during the 2013 field season. Control program was implemented in three orchards of mixed apricot varieties. Ceranock traps were hung in each tree of two separate orchards. Delta and McPhail traps were used to monitor Medfly population density in each treated and control orchards. Results indicated that Medfly activity in apricot orchards started during the last week of April coincided with the beginning of maturity for fruits of early varieties. The total of trapped insects in monitoring traps after one week of Ceranock application were 0, 1 and 31 adults for the 1st, 2nd and the control orchards, respectively. Three weeks later and on, the number of trapped adults started to increase dramatically. At the end of apricot season and after 45 days of Ceranock trap application, the number of trapped insects in monitoring traps reached 110, 111 and 2,349 adults/week, respectively, for the 1st, 2nd and 3rd orchard. The use of Ceranock traps reduced Medfly population density by 86%-97%. The percentage of fruit injuries in early maturing varieties were 0.75%, 1% and 34% for the 1st, 2nd and control orchards, respectively. While, late varieties were 2% and 3% for 1st and 2nd orchards, and 69% for the control. The percentage of reduction in fruit damages reached to 95% and 97%, respectively in the 1st and 2nd orchard. The results of this study demonstrate clearly the efficacy of Ceranock bait station, ＂attract and kill＂ system as a control measure for Medfly in apricot orchards.     

Fate of Fluazinam in Pepper and Soil After Application

To discover the fate of fluazinam after its application in pepper field, an efficient residual analytical method for determining fluazinam in pepper and soil was developed. The samples were extracted by acetone, cleaned up by solid-phase extraction （SPE） florisil cartridge, and determined by gas chromatography with electronic capture detector （ECD）. The recoveries ranged from 80 to 94.6%, with repeatability relative standard deviation ≤9.3% at spiking levels of 0.1-1 mg kg^-1. The residue dynamics of fluazinam in pepper and soil were studied in a field plot. The experiment data showed that the halflives of fluazinam in peppers and soils were 2.5-3.7 days and 1.2-4.2 days, respectively. When the pepper was treated by fluazinam 50% suspension concentrate （SC） at 495 g ha^-1 4 times at 7-day intervals, the fluazinam in pepper on the 7th day after the last application was all below 0.06 mg kg^-1, which was below the maximum residue limit （MRL） fixed in Korea （0.3 mg kg^-1）. It is implied that fluazinam in pepper is nonpersistent. The results suggested that fluazinam 50% SC should be used in a pepper field at most for 4 times, and the pre-harvest interval should be 7 days.     

Study on the Quantity Dynamic Changes of Heterobacteria and Vibrios in Larvae Industrialized Culture System

[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp.[Method] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system.[Result] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius,then their number would increase with growth. During whole rearing period,both heterobacteria in larvae,vibrios in water would increase by one order of magnitude,while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude.There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait.The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively,while the correlation among heterobacteria,vibrios in living bait and larvae,water were weak or negative.[Conclusion] There was a dynamic relation between water and larvae in rearing period,and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus,besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.     

工厂化育苗养殖体系内细菌数量动态变化研究(英文)

[Objective] The dynamic change of heterobacteria and vibrios in larvae industrialized culture system was studied to provide scientific reference for healthy cultivation of shrimp.[Method] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were monitored in larvae industrialized culture system.[Result] The heterobacteria,vibrios and pathogenic vibrio parahaemolyticus were the most in fertilized eggs of shrimp but the least in nauplius,then their number would increase with growth. During whole rearing period,both heterobacteria in larvae,vibrios in water would increase by one order of magnitude,while both vibrios in larvae and heterobacteria in water would increase by two orders of magnitude.There were many heterobacteria and vibrios but few vibrio parahaemolyticus in living bait.The correlation coefficients between larvae and heterobacteria and vibrios in water were 0.704 and 0.840 in culture system respectively,while the correlation among heterobacteria,vibrios in living bait and larvae,water were weak or negative.[Conclusion] There was a dynamic relation between water and larvae in rearing period,and restrictly control of culture condition would restrain the occurrence of disease caused by vibrio parahaemolyticus,besides that bacteria number in bait was not obviously correlated with bacteria nubmer in culture system.     

Fruit Yield and Quality,and Irrigation Water Use Efifciency of Summer Squash Drip-Irrigated with Different Irrigation Quantities in a Semi-Arid Agricultural Area

Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efifciency （IWUE） of summer squash responses to different irrigation quantities were evaluated with a ifeld study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefifcients （Kcp, 100% （Kcp1）, 85% （Kcp2） and 70% （Kcp3））. Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield （80.0 t ha-1） was determined in the Kcp1 treatment, which applied the highest volume of irrigation water （452.9 mm）. The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha-1, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment （176.6 kg ha-1 mm-1）, it was statistically similar to the value for Kcp3 treatment （157.1 kg ha-1 mm-1）. Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 （44.27 μg gallic acid equivalents （GAE） mg-1 fresh sample） and in the Kcp2 （84.75%） treatments, respectively. Major （Na, N, P, K, Ca, Mg and S） and trace （Fe, Cu, Mn, Zn and B） mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were signiifcantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions.     

Unconditional and Conditional QTL Mapping for Tiller Numbers at Various Stages with Single Segment Substitution Lines in Rice （Oryza sativa L.）

Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand ＂static＂ and ＂dynamic＂ information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.     

Peach yield and fruit quality is maintained under mild deficit irrigation in semi-arid China

We conducted a two-year study of deficit irrigation impact on peach yield and quality in semi-arid northwest China. Over two years, four-year-old peach trees were irrigated at 100, 75, 50 and 25% of peach evapotranspiration(ET_c), here, ET_c= Coefficient(Kc)×Local reference evapotranspiration(ET_o). During the April-July fruit production season we measured root zone soil water depletion, sap flow velocity, net photosynthetic rate(P_n), transpiration rate(T_r), stomatal conductance(G_s), water use efficiency(WUE=P_n/T_r), fruit quality, and yield under a mobile rain-out shelter. Increased soil water depletion reasonably mirrored decreasing irrigation rates both years, causing progressively greater water stress. Progressive water stress lowered G_s, which in turn translated into lower T_r as measured by sap flow. However, mild deficit irrigation(75% ET_c) constricted T_r more than P_n. P_n was not different between 100 and 75% ET_c treatments in both years, and it decreased only 5–8% in June with higher temperature than that in May with cooler temperature. Concurrently under 75% ET_c treatment, T_r was reduced, and WUE was up to 13% higher than that under 100% ET_c treatment. While total fruit yield was not different under the two treatments, because 75% ET_c treatment had fewer but larger fruit than 100% ET_c trees, suggesting mild water stress thinned fruit load. By contrast, sharply decreased T_r and P_n of the driest treatments(50 and 25% ET_c) increased WUE, but less carbon uptake impacted total fruit yield, resulting 13 and 33% lower yield compared to that of 100% ET_c treatment. Irrigation rates affected fruit quality, particularly between the 100 and 75% ET_c trees. Fewer but larger fruit in the mildly water stressed trees(75% ET_c) resulted in more soluble solids and vitamin C, firmer fruit, and improved sugar:acid ratio and fruit color compared to the 100% ET_c treatment. Overall, trees deficit irrigated at 75% ET_c maintained yield while improving fruit quality and using less water.