Drip irr tomato

Research on suitable drip irrigation schedule for tomato Tran Thai Hung1 2*, Xing Wengang1, Hoang Cam Chau1 Agricultural Engineering Department, Hohai University, Nanjing 210098, China; Southern Institute of Water Resources Research, Ho Chi Minh City ,Vietnam Ha Noi Water Resources University, Ha Noi, Vietnam Abstract Drip Irrigation Technique is a basic form of Water Saving Irrigation Previous researches of drip irrigation technique in greenhouse were not paid more attentions in detailed calculating and researching on suitable schedule as appropriate drip irrigation frequency and water amount by each growing stage The experimental research on suitable drip irrigation schedule for tomato was carried out in the Greenhouse located in Water Saving Park of Jiangning Campus, Ho Hai University, Nanjing, China from February to July, 2007 to contribute in assessing effect of drip irrigation technique for water utilization issue, crop development and productivity, especially to find suitable drip irrigation schedule for tomato by growing stages The experimental model of drip irrigation for tomato was designed with nine treatments and one control following three irrigation frequencies and three levels of water amount Drip irrigation water amount for tomato was calculated by Panman method based on combination between evapotranspiration changed by daily evaporation measurement results and each growing stage Results of experimental model showed that drip irrigation has made the real effect for tomato development process and yield as well as water saving issue With traditional irrigation method, all tomato component and yield results were lower than those ones in nine treatments From measured and analyzed results of tomato growing as well as irrigation water requirement, the irrigation schedule is established with 3-day frequency and water level of 100% evapotranspiration to serve agricultural production development and to perform specific researches Keywords: Drip irrigation; Irrigation frequency; Irrigation amount; Tomato; Irrigation schedule I Introduction Nowadays, exploitation and utilization of water and soil resources are continuously increasing at the same time with quick development of mankind They lead to maximum exploitation of natural resources, environmental pollution and the balance between natural exploitation and rehabilitation broken Therefore, natural resources research, in which are water and soil, has been cared and researched on every fields very deeply and extensively by scientists and nations with purposes to analyze, to assess as well as to recommend of resource exploitation and utilization They have contributed very largely to developing and protecting task of those resources unshakably With agricultural development, water and soil are utilized very much to make production for society Effective and reasonable water utilization, first and foremost crop irrigation, has been paid more especial attention because of its importance and need Now the tendency to develop irrigation in many countries is the sensible exploitation of existing hydraulics project systems and strengthening on the depth of irrigation techniques and methods to raise economic effect based on the utilizable effect of water resources [1, 2, 3] * Corresponding author Water saving irrigation technique is the best water supply technique and contributing to raise productivity and quality of crops considerably Therefore, the developmental requirement of water saving irrigation technology is very necessary and developing very strong in the World now It makes high economic effect and will open up considerable prospects to develop industrial crops, fruit-trees, vegetables and other crops what have highly economic value Most nations in the world have already applied little or much of water saving irrigation technologies According to the FAO’s estimation, there have been more million hectares of cultivated crops being irrigated by these technologies United States of America, Israel, Australia, German, Italy, Hungary are countries with much experiences and achievements in researched and applied fields of water saving irrigation technologies [4] Drip Irrigation Technique is a basic form of Water Saving Irrigation or Micro-irrigation that crop stump area is supplied water in the form of every drip on the ground by dripper directly and continuously Drip irrigation performance depends very little on natural elements: shape and slope of terrain, soil texture and composition, temperature, especially without being affected by wild like sprinkler irrigation [4, 5, 7, 8] Previous researches of drip irrigation technique in greenhouse were not paid more attentions in detailed calculating and researching on suitable schedule as appropriate drip irrigation frequency and water amount by each growing stage Therefore this research was carried out to satisfy those issues with calculation of drip irrigation water amount based on combination between evapotranspiration changed by daily evaporation measurement results and outside form of tomato by each growing stage II Materials and methods 2.1 Research objectives: Previous researches of drip irrigation technique in greenhouse were only carried out in irrigating following fixed water amount for the whole crop and then determining total yield for comparison They were not paid more attentions in detailed calculating and researching on suitable schedule as appropriate drip irrigation frequency and water amount by each growing stage Therefore, this experimental research on suitable drip irrigation schedule for tomato to achieve main objectives as following: (1) Analyze and assess the active impact of drip irrigation technique to tomato development, productivity and quality Determine the best development and yield as well as water used efficiency (2) Analyze and determine suitable drip irrigation schedule for tomato including: irrigation water amount and frequency by every growing stages (3) Analyze and assess the advances as well as restrictions of drip irrigation technique for agricultural production need to be surmounted 2.2 Approachability and research methods: Approachability and research methods were established for helping experimental performance following a system of practice combining with modern science and technology inheritance, knowledge, experience, multi-target water resources management and effectively utilizable and exploitable models to develop society-economy and to protect stable ecological environment Research techniques were utilized including utilization of machines and instruments in establishing experimental model, measuring and recording data in the field and in the laboratory; doing statistically of data surveyed and recorded from the experimental model; calculation theory of water requirement for drip irrigation technique The scientific and technical development and the market mechanism are causes of: Changes of cultivated system models in large-scale The strong exploitation of resources making losses of natural balance Research object Approach practice systematically, comprehensively and generally Water saving irrigation Inherit the modern science and technology and database given selectively Increase of crop productivity and quality Approach methods of water resources management and multi-target of effectively utilizable and exploitable models of water resources  Concept and definition of water saving irrigation technique and drip irrigation one  The role and development of drip RESEARCH ON SUITABLE DRIP IRRIGATION SCHEDULE FOR TOMATO irrigation technique in the present and in the future  Basic scientific to calculate, design the experimental model of drip irrigation for tomato Protection of ecological environment  Establishment of the experimental model of drip irrigation for tomato  Methodology Approach is based on the stably developmental principle Stable and unshakable development Require the solution of saving and effective utilization and exploitation of water resources Determine again calculation norms of irrigation and drainage for crops Figure 2-1: The sketch of research approachability development on suitable irrigation schedule for water saving irrigation technique in general and drip irrigation in particular Exhausted exploitation and utilization water-soil; water pollution Water supply solution for crops by the modern science and technology Determination of norms of crops irrigation and drainage APPLICATION OF WATER SAVING IRRIGATION TECHNIQUES IS THE MOST REASONABLE SOLUTION Overview, concept and definition DRIP IRRIGATION TECHNIQUE Planning and designing process of the experimental model of drip irrigation schedule for tomato Scientific bases serves for researching on drip irrigation schedule for tomato Social-economic developmental demand, reasonableeffective utilization and exploitation in order to protect watersoil resources Natural conditions (climate, edaphology, water-soil resources…) Methods and techniques of research and calculation Features of water saving irrigation techniques Design, build and management of exploitation projects to serve in supplying water for crops Technique of agricultural production and standards of product quality Following crop water requirement by growing stages Following weather conditions, optimal soil moisture limit Following integrated utilization requirement of water resources and protection of ecological environment unshakably Propose and select the suitable experimental model of drip irrigation technique Determination of basic technical parameters of drip irrigation technique ESTABLISHMENT OF THE EXPERIMENTAL MODEL TO RESEARCH ON SUITABLE DRIP IRRIGATION SCHEDULE FOR TOMATO Data observation and measurement Data collection and analysis RESULT Figure 2-2: The sketch of research methods and techniques 2.3 Description of experimental site: The Field study was carried out in the Greenhouse of the Water Saving Park in Jiangning Campus, Hohai University (latitude 31°57' N, longitude 118°50' E), Nanjing, China, in the period February to July, 2007 It belongs to the North subtropical monsoonal climate zone, four seasons clearly demarcated Annual average temperature is 16oC; absolute maximum one is 43oC; average daily one is 28.1oC in the hottest months and -2.1oC in the coldest months Sunlight time is 6:30 and the latest sunset is 17:30 Annually there are 117 rainy days; the rainy season is from the end of June to the middle of July, annual even precipitation is 1,106mm, maximum average humidity is 81% The weather feature in the Greenhouse was different from outside as temperature, air humidity, wind, rainfall but outside weather directly influenced to inside one Table 2-1: Some weather features in the Greenhouse Weather Max 9:00 Temperature 32.0 12:00 Temperature 33.0 Humidity 92.51 Humidity 96.14 15:00 Temperature Humidity 32.0 96.18 Min 12.0 54.09 15.0 62.04 13.0 60.29 Average 25.8 78.50 27.9 77.57 26.3 80.03 Remarks Soil in the experimental model had heavy and strong texture, rather yellow or light color When the soil was dry, on the surface appeared very much rifts Table 2-2: Some properties of soil (0 - 0.3m deep) Item Soil type Bulk density (g/cm3) Value Clay – Loam Item Field capacity (%) 1.35 pH Value 25.8 6.4 Te mperature in the Gre e nhouse Temp erature (0 C) 35 30 25 20 15 10 /2 /3 /10 /17 /2 5/ 5/ 5/ 15 5/ 2 5/2 ta :0 /5 /12 ta 12 :0 /19 /2 7/ 7/ 10 7/ 17 7/ 7/ 7/ 10 7/ 17 7/ ta 15:0 Date Humidity in the Gre e nhouse Humid ity (%) 10 80 60 40 20 /2 /3 /10 /17 /2 5/ 5/8 5/ 15 5/ 2 5/2 Humid ity (9 :0 ) /3 /12 /19 /2 Date Humid ity (15:0 ) Evaporation in the Gre e nhouse Evap o ratio n (mm) 3 /2 /5 Humid ity (12 :0 ) /10 /17 /2 5/1 5/8 5/15 5/2 5/2 /5 /12 /19 /2 7/3 7/10 Evap oratio n (mm) 7/17 7/2 Date Figure 2-3: Temperature, humidity and evaporation process in the Greenhouse 2.4 Design and build of the experimental model in the Greenhouse: Based on weather features, soil, crop type, equipment and method of irrigation, the experiment was designed with three irrigation frequencies: (A): 2days, (B): 3days; (C): 4days and three levels of water amount: (a): 1.2Dirr, (b): 1.0Dirr, (c): 0.8Dirr Therefore, there were nine treatment blocks and a control block In the control block, water irrigation amount was calculated and irrigated like traditional irrigation and frequency was 4days Table 2-3: Experimental designing of drip irrigation schedule for tomato Frequency A (Two days) B (Three days) C (Four days) a (High level: 1.2Dirr) BLOCK TREATMENT Aa BLOCK TREATMENT Ba BLOCK TREATMENT Ca b (Medium level: 1.0Dirr) BLOCK TREATMENT Ab BLOCK TREATMENT Bb BLOCK TREATMENT Cb c (Low level: 0.8Dirr) BLOCK TREATMENT Ac BLOCK TREATMENT Bc BLOCK TREATMENT Cc Water level Traditional Irrigation BLOCK 10 CONTROL CT (Four days) Block dimensions were 6.0m long and 1.0m wide; trench dimensions were 0.3m wide and 0.2m deep Soil surface level of all blocks was established with the same height The main pipeline with inside diameter of 25mm was connected to water supply system directly and the branch ones attached drippers with inside diameter of 15mm was connected to the main one and then irrigated water for trees directly The branch pipelines were installed 60cm apart among the two lines in each block Every branch pipeline with 16 drippers was put closely with tree stumps and drippers were 0.4m spacing in each line [9, 10] Beidousan-F1 variety was used as the crop material which was sown on February 25th, 2007 One and half month old seedlings were transplanted into plots In every block, there were two tomato rows with 16 trees in one row Each block was divided into three parts, the first fivetomato of two rows was part 1, the second one was part and the last six-tomato of two rows was part In each part there were three tomatoes selected for measuring and observing data * Calculation of water requirement of tomato: In the drip irrigation method, only a small soil part round the tree stump is made wet, so the determination of irrigation water requirement for crops need to be calculated differently with other normal calculation methods Water requirement of tomato is included water in the body, evapotranspiration and a part for supplying to flower and fruit While tomato has not got flower and fruit, water is only in the body and evapotranspiration Since tomato has flower, another part of water will be used to help flower and fruit develop so water requirement will increase Nearly the harvest time, water requirement need to decrease for fruit to mature and synthesize sugar and vitamin Therefore, water requirement of tomato was calculated by Panman method from daily evaporation measurement and water requirement coefficient by growing stage (Tg) was established based on every growing stage and outside form of tomato to ensure tomato developing well and getting high yield Field evaporation in the experimental model is calculated as following: [6] ET  ETpan * Kpan (mm) (2.1) Daily evapotranspiration is calculated at climax period of tomato as following: S [7] ETo  (0.1  ) * ET (mm) (2.2) 100 Calculative water requirement for tomato by drip irrigation technique is showed: (mm) (2.3) Dirr  Tg * ETo Water amount of each block for controlling irrigation was calculated as: W(i) = m(i) * Dirr (mm) (2.4) Where: W(i): Water amount of each block for controlling irrigation (mm); m(i) : The level establishment coefficient of irrigation; m1 = 1.2 (high level); m2 = 1.0 (medium level); m3 = 0.8 (low level); Dirr: Calculative water requirement for tomato by drip irrigation technique following growing stages (mm); S (%): The vertical leaf canopy percentage of tree on the soil surface at 12:00 ETpan: Evaporation of Pan was daily measured (mm); Kpan: Coefficient of Pan in the Greenhouse, Select Kpan = 0.8 [6]; Tg : Water requirement coefficient by growing stages; During the experimental time, growing stages were divided into periods with corresponding values of Tg as following table 2-4 Table 2-4: Water requirement coefficients following growing stages Period March 27th to April 15th, 2007 April, 16th to April 30th, 2007 May, 1st to May 10th, 2007 May, 11th to May 31st, 2007 June, 1st to June, 20th, 2007 June, 21st to July 27th, 2007 Tg Pre-irrigation controlled 1.00 1.25 1.50 1.25 1.00 2.5 Field study: Measurement of temperature, humidity and water table; Measurement of evaporation, water calculation and irrigation; Measurement of temperature, humidity and water table; Measurement of tree indexes by time; Harvest and weight of fruits; Collection, classification and analysis of data to help assessing experimental results more exactly; WATER TABLE SURVEY EVAPORATION MEASURMENT BRANCH OUTLET VALVES THERMOMETER THE SECOND ROW THE FIRST ROW BLOCK 10 BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK BLOCK PLACE PART 6m PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART PART 6m PART HEIGHT LEVEL CONTROL STAKES OUTLET VALVE FOR KEEPING RIPENING FRUIT AND EXPERIMENTAL EQUIPMENTS OBSERVED TREES SYSTEM CONTROL VALVE BRANCH CONTROL VALVES BRANCH PIPELINES WITH DRIPPERS Ø = 15mm WATERMETER MAIN PIPELINE Ø = 25mm WATER SUPPLY SOURCE 13m Figure 2-4: The sketch of the experimental model of drip irrigation technique III Results and discussions 3.1 Calculation and results of irrigation water requirements: Table 3-1: Total irrigation water amount (1) days Frequency days days Block 10 Block Block Block Block Block Block Block Block Block (4 days) Total water amount (mm) 228.717 196.153 163.589 229.197 196.553 163.909 228.861 196.273 163.685 274.333 Compared to Block 10 (%) 83.37 71.50 59.63 83.55 71.65 59.75 83.42 71.55 59.67 100.00 Total irri gation water amou nt (The whole experimental time) W ate r amount compared to Block 10 (The whole experimental time) (%) Amo unt (m m ) 10 300 90 50 80 70 200 60 50 150 40 10 30 20 50 10 0 10 10 B lo c k B lo c k Figure 3-1: Irrigation water amount and rate compared to Block 10 From table 3-1 and figure 3-1, they can be seen that total water amount of drip irrigation technique in every blocks (from Block to Block 9) was lower than the irrigation amount of traditional method (in Block 10) It is detailed as following: - With the high level: Total water amount in Block at 83.37%, Block at 83.55% and Block at 83.42% compared to block 10 at 100% amount Water saving amount was 45.616mm for Block 1, 45.136mm for Block and 45.472mm for Block compared to block 10 at 100% amount The difference of total irrigation water amount between three treatment blocks was very little and decreased as: Block > Block > Block - With the medium level: Total water amount in Block at 71.50%, Block at 71.65% and Block at 71.55% compared to block 10 at 100% amount Water saving amount was 78.180mm for Block 2, 77.780mm for Block and 78.060mm for Block compared to block 10 at 100% amount The difference of total irrigation water amount between three treatment blocks was very little and decreased as: Block > Block > Block - With the low level: Total water amount in Block at 59.63%, Block at 59.75% and Block at 59.67% compared to block 10 at 100% amount Water saving amount was 110.744mm for Block 3, 110.424mm for Block and 110.684mm for Block compared to block 10 at 100% amount The difference of total irrigation water amount between three treatment blocks was very little and decreased as: Block > Block > Block (1) Irrigation water amount of Block 10 was the greatest so water amount of other blocks (from Block to Block 9) were compared to it for finding differences of all treatments themselves 3.2 Effect of irrigation method, water quantity on tomato development and yield: On March 28th, 2007, the whole tomatoes in the experimental model were measured and recorded with beginning values about 11-16cm high as well as all other indexes as leaf, canopy dimension, body diameter In the last stage, all tomatoes had flowers and born fruits so most of tomato components (height, leaf and body diameter) developed slowly down On June 6th and June 7th, 2007 top of all tomatoes were cut away at the above opening flower layer for fruits developing well Measured results showed that there were three stages of development process, the first stage was from March 28th to April 20th, 2007 - tomato started developing, the second one was from April 20th to May 30th, 2007 - tomato developed very fast and the last one was from May 30th to June 5th, 2007- tomato developed slowly down a) Effect on height: From measured results and figure 3-2, they can be seen that effect of drip irrigation on height development of tomato between nine treatment blocks was little different but it was very obvious in comparison with block 10 The arranged order for development of tomato height was as following: Block > Block > Block > Block > Block > Block > Block > Block > Block > Block 10 He i ght de ve lopme nt of tomato on March 28th, 2007 Hei ght de vel opme nt of tom ato on April 20th, 2007 Heig ht (c m) 00 18 16 Heig ht (cm) 200 18 16 14 12 10 14 12 10 80 60 40 20 80 60 40 20 0 10 B lo ck Hei gh t de vel opme nt of tom ato on May 15th , 2007 200 18 16 14 12 200 18 16 10 10 80 60 10 B lo ck 10 B lo ck Hei gh t de vel opme nt of tom ato on Jun e 5th , 2007 Heig ht (cm) Heig ht (cm) 14 12 80 60 40 20 40 20 10 B lo ck Figure 3-2: Height development process of tomato b) Effect on total leaf numbers and leaf canopy dimension: Development of total leaf numbers and leaf canopy dimension of tomato concerns evapotranspiration and photosynthesis When leaf develops well, it will make evapotranspiration and photosynthesis increase fast, decrease evaporation of the ground This means that metabolic capacity of tomato will increase and help tomato develop well and get high yield From measurement results and figure 3-3, they can be seen that there were three growing stages: the first stage was from March 28th to April 20th, 2007, the second one was from April 20th to May 30th, 2007, and the last one was from May 30th to June 5th, 2007 The development process of leaf numbers and leaf canopy dimension as well as leaf petal size and thickness in nine treatment blocks were rather equal and better than those ones in Block 10 The developmental arranged order of tomato leaf numbers and canopy dimension was as: Block > Block > Block > Block > Block > Block > Block > Block > Block > Block 10 Table 3-2: Development of leaf canopy dimension of tomato (unit: cm*cm) March 28th, 2007 18*16 19*15 18*15 18*14 19*16 18*14 19*17 18*15 17*13 18*15 Block 10 April 20th, 2007 43*34 42*34 42*34 46*35 50*43 46*37 45*40 45*36 43*38 34*28 April 30th, 2007 57*52 58*56 52*49 56*51 61*55 56*52 60*54 57*51 56*54 45*40 May 15th, 2007 84*77 87*81 87*80 83*76 88*81 84*76 86*81 85*77 84*80 69*63 Total le af n um be rs of tomato on March 28th , 2007 May 30th, 2007 103*94 104*96 102*95 102*94 104*97 101*94 103*97 102*95 102*97 87*79 June 5th, 2007 Remarks 104*96 105*97 103*97 103*94 105*98 104*95 103*98 104*96 103*98 90*83 Total l e af n um be rs of tomato on April 20th , 2007 Leaves 30 28 26 24 22 20 18 16 14 12 10 Leaves 30 28 26 24 22 20 18 16 14 12 10 2 10 B lo ck Total l e af n um be rs of tomato on May 15th , 2007 Le aves Le aves 30 28 26 24 22 20 18 16 14 12 10 30 28 26 24 22 20 18 16 14 12 10 2 10 B lo ck 10 B lo ck 10 B lo ck Total l e af n um be rs of tomato on Jun e 5th, 2007 Figure 3-3: Development of leaf numbers by time of tomato c) Effect on tomato body diameter: From measurement results and figure 3-4 of development process of tomato body diameter, they can be seen that the development process of tomato body diameter in nine treatment blocks was faster and more equal than those ones in Block 10 The arranged order for development of tomato body diameter was as following: Blocks 1, 2, 3, 4, 5, and > Blocks and > Block 10 Tomato body diame te r on March 28th, 2007 Diameter (mm) 20 18 16 14 12 10 2 Tomato body diame te r on April 20th , 2007 Diameter (mm) 20 18 16 14 12 10 10 B lo ck Tomato body diame te r on May 15th, 2007 Diameter (mm) 20 18 16 14 12 10 2 Diameter (mm) 20 18 16 14 12 10 10 B lo ck 10 B lo ck 10 B lo ck Tomato body diame te r on June 5th, 2007 Figure 3-4: Tomato body diameter 10 3 d) Effect on flower layers and fruit development: Experimental results showed that flowers in nine treatment blocks opened more equally and soon than those ones in Block 10 Some blocks had tomato with sooner opening flower as Blocks 1, 2, and Most tomatoes in nine treatment blocks had flower layers but at Block 10 there was no anyone Flower layer height of tomato was very different However they did not impact on fruit development and yield Fruits in nine treatments blocks developed more equally, quickly and concentratively than fruits at block 10 about size, growing and mature time The arranged order for flower layers and fruit development was as following: Blocks 1, 2, 3, 4, and > Blocks 7, and > Block 10 Table 3-3: Fruit development periods (from started fruiting to started harvesting) Layer Time Block Block Block Block Block Block Block Block Block Block 10 Layer From To May 3rd , 2007 June 18th, 2007 May,4th, 2007 June 18th, 2007 th June 18th, 2007 May , 2007 May 8th, 2007 June 20th, 2007 nd May,2 , 2007 June 16th, 2007 May 5th, 2007 June 16th, 2007 June 16th, 2007 May 4th, 2007 th May , 2007 June 18th, 2007 May 9th, 2007 June 18th, 2007 th May 18 , 2007 June 30th, 2007 Layer From To May 7th, 2007 June 30th, 2007 May 8th, 2007 June 30th, 2007 th May 10 , 2007 June 30th, 2007 May 13th, 2007 July, 6th 2007 May 5th, 2007 June 30th, 2007 May 9th, 2007 June 30th, 2007 May 7th, 2007 June 30th, 2007 th May 14 , 2007 June 30th, 2007 May 16th, 2007 June 30th, 2007 th May 24 , 2007 July 3rd, 2007 Flowe r laye r numbe rs of tom ato on April 25th, 2007 Layer numb ers Flowe r l aye r nu mbe rs of tomato on May 5th , 2007 Layer numb ers 7 6 5 4 3 2 1 0 Layer From To May12th, 2007 July 7th, 2007 May 14th, 2007 July 11th, 2007 th May 15 , 2007 July 8th, 2007 May 18th, 2007 July 11th, 2007 May 11th, 2007 July 6th, 2007 May 16th, 2007 July 11th, 2007 May 14th, 2007 July 7th, 2007 th May 19 , 2007 July 8th, 2007 May 20th, 2007 July 7th, 2007 th May 30 , 2007 July 7th, 2007 10 10 B lo ck Blo ck Layer numb ers Fl owe r l aye r nu mbe rs of tomato on May 25th, 2007 Layer numb ers 7 6 5 4 3 2 Flowe r l aye r n u mbers of tomato on Ju n e 5th , 2007 1 0 10 10 Blo ck Blo ck Figure 3-5: Flower layer numbers of tomato e) Effect on yield: * Fruit weight: Experimental results showed that in the first three layers, fruit weight (from 100g to 300g) of Blocks: 2, 3, 4, and was rather equal and better than other blocks Fruit weight over 300g was mainly in Blocks: 3, 5, and In nine treatment blocks, there was no fruit with weight under 50g but that was 14% at Block 10 Total yield by layer was rather different Total yield of the first layer was the highest Yield of the second layer was the second and then was the third layer Total yield of the 4th, 5th and 6th was the lowest Total yield of tomato in Block was the highest, the next was Block 6, the third was Block and the lowest was in Block 10 In comparison between total yield and irrigation water amount of each block, they can be seen that: 11 - With the same irrigation frequency: For 2-day frequency, the lower irrigation water amount, the higher tomato yield For 3-day frequency, tomato yield of medium irrigation water amount (Block 5) was the highest and the next was at low irrigation water amount (Block 6) For 4-day frequency, tomato yield of medium irrigation water amount (Block 8) was the highest and the next was at high irrigation water amount (Block 7), yield of Block was the lowest Yield result of block can be understood that with low water level and long frequency would make tomato not have enough water to feed body, flower and fruit in developing - With the same irrigation water level: Irrigation water amount of every blocks in each private group was rather equal but total yield in each block was very different For all levels, tomato yield of 3-day frequency (Blocks 4, and 6) was the highest, the next was at 2-day frequency (Blocks 1, and 3) and the lowest was at 4-day frequency (Blocks 7, and 9) Therefore, effect of water saving and increasing yield is obvious following the medium and low water level combined with the medium and short frequency The arranged order for total yield was as following: Block > Block > Block > Block > Block > Block > Block > Block > Block > Block 10 Table 3-4: Fruit weight rate by layer Values Block (%) Block (%) Block (%) Block (%) Block (%) Block (%) Block (%) Block (%) Block (%) Block 10 (%) 20 54 23 58 33 67 22 3 56 36 0 43 46 58 25 20 58 22 0 18 50 29 20 47 33 0 40 54 0 21 55 24 0 21 55 24 0 23 48 23 30 60 10 0 10 64 26 0 16 63 22 0 12 69 15 21 46 29 33 62 0 46 54 0 39 44 17 0 38 50 13 0 36 52 12 0 36 50 14 0 13 57 30 0 24 68 4 16 67 17 0 50 41 0 31 50 15 56 44 0 Block Block Block Block 10 The First Layer Weight < 100g 100g ≤Weight