STUDY REVEALS YIELDS OF 80 TO 110 TONNES PER HECTARE
Report on the study carried out on five varieties of melon’s in greenhouses using pruning and tutoring techniques
By L . Bringas According to a study carried out by trellis netting manufacturer in conjunction with UAS (Universidad Autonoma de Sinaloa), yields of 80 to 110 tonnes per hectare of improved-quality melons can be achieved by cultivating the crop in greenhouses,.
Felipe Ayala, a professor-investigator working in conjunction with agronomists Juan Gabriel López from manufacturer of melon netting and Hernán Sotelo from UAS’s Faculty of Agronomy, carried out a test with five commercial varieties of melon, using a soil-based cultivation system, of one or two stems, growing the crops in a vertical direction using netting and raffia tutoring.
“The main objective of the study test,” says Professor Ayala, “was to test the potential of some varieties of cantaloupe and honey dew melons, growing the plants vertically using trellis netting, which gives better support than raffia tutoring.”
Those who carried out the test explain that when growing melons in open fields, there are various technical problems, such as some varieties failing to adapt and inadequate fertilisation that limits the fruits’ development. In addition, they also highlight the damage that occurs from contact with the moist ground, scorching from the sun, weeds, and the outbreaks of pests.
“An alternative that we have found to be effective in dealing with these problems is to cultivate the crop in greenhouse conditions, using farming practices and techniques such as pruning and tutoring, direct sowing into bare soil, with a distance of 1.6m between the planting beds and 33cm between the plants in single rows, to achieve a density of 18,750 plants per hectare.”
Producing melons in greenhouses is conducive to the adaptation of high-yield varieties, improving pollination and avoiding the damage caused by sun scorches, weeds and outbreaks of pests.
In the study report by UAS, it mentions that the production period began at the beginning of March with direct planting into clay soil, with low levels of organic matter present in the soil and a mildly alkaline pH. When the plants began to flower (in the second week of April), Vegetable trellis netting and raffia was installed. For the netting, stakes were placed at 2.5m intervals to support the first segment of netting at a height of 1.5m. When the plants were approaching this height, a second batch of netting was installed which was fastened to the support system and then two segments were fixed together on the top to make a support frame. One or two threads of raffia are wrapped around each plant depending on how many stems it has, fastening them to the base of the plant using rings, and to the wires in the upper section. Juan G. López explains that, in order to direct the growth of the one-stemmed plants, all of the stems branching out from the main stem are removed during the first fifty centimetres of growth. “Above that height, all branching stems were pruned above the leaves which were growing after the fertilised buds with new fruits”, explains the melon trellis factory’s representative. For the two-stemmed plants, as well as the main stem, a primary stem was left branching out from the lower part of the main stem, and both were pruned to remove all their secondary stems as was the case with the one-stemmed plants.
By providing the necessary water and nutrients for fertigation appropriate to the development stage, the production cycle continued for a total of twenty weeks. “210 units of nitrogen, 150 units of phosphorus, 340 units of potassium, 55 units of magnesium and 180 units of calcium were applied, for a crop which produced stems of up to 6.5m in length and medium to large-sized fruits which yielded an average of 7 to 12 kilos per metre squared,” says Juan G. López.
As regards the length of the stems, the test showed that crops pruned back to two stems reached average lengths of 5.2m with raffia tutoring, and 5m with netting. For plants pruned to a single stem, lengths were 4.4m with raffia and 4.6m with netting. As regards the diameters, the crops pruned to one stem produced sizes a little wider than 1.2cms, compared to 1.05cm for the crops pruned to two stems, with both widths not being affected by the method of tutoring.
Using HORTOMALLAS support netting and pruning back to one stem, yields of 6,543 Bruce-type cartons.
Harvesting of the fruits began at the end of May and lasted for 57 days. The highest yields were seen with the Acimarron and Copa de Oro varieties, both grown on one stem and using netting to tutor. It is important to note that both the size and the quality of the fruits exceeded expectations, as bigger fruits with even colour and patterning were harvested, which averaged 9-10 Brix degrees for the cantaloupes and 12.5 for the honey dews.
Thanks to this study test, it has been shown that vertical growth of melon plants using tutoring improves plant health and provides better ventilation for the foliage. By the same token, the best yields and fruit quality were seen to be directly related to better exposure of the leaves to sunlight.
Professor Ayala comments that pruning melon crops stems regulates their growth and stimulates the development of their fruits. “We had excellent flowering, which we developed by securing the plants well and ensuring good pollination of the fruits, which matured very fast.” Those carrying out the test said that vertical growth allowed for well-formed vegetative development and better ventilation, which in turn facilitated the application of various plant-health treatments.
HORTOMALLAS, S.A. de C.V. Credits PRODUCTORES de HORTALIZAS SEPTIEMBRE 2002