High Quality And Yielding Cultivation Techniques Of Watermelon

Summary watermelon is ranked one of the top 10 fruits in the world market. China is the largest producer for watermelon, accounting for approximately 45% in terms with total acreages and yield. However, watermelon fruits produced in China is relatively lower either in quality or in economic returns. With the entrance of world trade market, domestic watermelon markets are challenged with global competition. Hence, it is very imperative to improve fruit quality. Meanwhile, domestic consumers are also seeking higher quality fruits with the increasing living standard and diversified supply of fruits available. As aforementioned, it is essential to start investigation on high quality and yielding cultivation techniques.This research is practiced aiming at making clear the main properties of high quality watermelon cultivar "Zaojia" and grafted ones by using various stocks. The influence of culture parameters on quality and yield is investigated and corresponding high yield, and high quality sustainable system has been established. The main results are as follows: (1) Watermelon cultivar "Zaojia" is of early maturity, high earlier yield and superior quality with high sugar content and good flavor. It is an ideal cultivar for early protection culture. (2) Yield and economic gains are varied significantly by cultivating growing period, which is 86.3% and 254.0% higher respectively than mulch cover alone. Accordingly, second largest yield and income has been obtained by two-layer plastic cover, 43.2% and 71.8% higher respectively than single mulch cover. (3) Additional application of CO2 aerial fertilizer on seedling-raising stage is obviously capable of enhancing seedling quality that shows higher plant height, big stem diameter, good formation of hairy system, and dark green leaf color. Furthermore, it is more effective to apply CO2 aerial fertilizer in the afternoon than in the early morning, by which early maturity, higher quality and yield are achieved. In addition, more female flowers are generated than those non-treated ones. The plants treated with CO2 aerial fertilizer showed 20% more fruiting on single plant and increase of 0.25 kg for single fruit on the average resulting in 8.7% increase in total yield per 667 m2. (4) The total yield varies greatly with different training practices and planting density. It is decreased accordingly with the increase of density at which the highest yield isobtained at the density of 200 plants per 667 m2. However, no significant differences in yields are observed when planting density ranges from 200 to 250 plants per 667 m2. (5) In adequate application of fertilizers, more fruit-setting and bigger fruit that leads to higher yield are obtained, whereas in insufficient supply of fertilizers, such as less potassium and more nitrogen, smaller fruits and lower fruit-setting rate is found that result in low yield and inferior quality. In our experiment, the favorable ration of N: P:K is 2.1:1:1.3 in which the highest yield is achievable. (6) The resistance to fusarium wilt, yield and fruit quality are improved by using minature watermelon specialized stock cultivars or 'Shengtongli' stock cultivar. The earlier yield is increased with planting density ranging from 150 to 600 plants per 667 m2 when grafting 'Zaojia' cultivar is trained with 3 vines. Moreover, enhanced application of potassium and organic fertilizers is beneficial for higher yield with bigger fruit and higher quality. In addition, the effect of enhanced application of potassium on yield and quality is more profound than phosphorous application.