The Effect of Planting Space and Harvesting Method on Quantitative and Qualitative Traits of Tomato (Lycopersicon esculentum Mill.)

One time tomato harvesting, in addition to labor saving, provides a possibility of increasing the cultivated area which lead to increase the total output (1). Varieties of tomato that has multiple harvest usually have a lower density in farm compared to one time harvest (2). In the late 1940s, the processing tomato industry in California was concerned that expected shortage of labor would prevent harvest of its increasing tomato production. Commercial use of the new variety and the new harvesting method, began in early 1960s. New harvesting method had a labor requirement of 2.9 hours per ton, compared with 5.3 hours per ton for hand-harvest in several times. Total labor use for the crop dropped from 13.5 million hours in the hand-harvest years to about 3.8 million hours per year in 1997, while fruit yield increased 4-fold (3). This study was carried out in two years (2010-2011) at Mazrae Nemone Astan Ghods Razavi using a factorial experiment based on randomized complete block design with 4 replications. The first factor was planting space within row at three levels including 20, 30 and 40 cm and the second factor was harvesting method at two levels including multiple and one time on tomato variety hypeel 347. Measured traits included fruit number per plant, fruit weight per plant, yield, as quantitative also pH, brix as qualitative and labor consumption per each ton of harvested fruit were investigated. Each plot consisted of 5 rows with a length of 6 meters, the plant in the row bilaterally (a total of 10 lines per plot) were planted. Drip irrigation method was performed using the T-tape with 1.6 liters per hour. Harvesting started in mid-September and ended in late October. Fully ripe and healthy fruits were harvested and rotten fruits were not collected. Quantitative traits Analysis of variance showed that the effect of year and planting space on all quantitative traits was significant while harvesting method significantly affected fruit weight per plant and fruit yield. Interaction between year and planting space had significant effect on the fruit number and weight per plant. Moreover, interaction of year and harvesting method had a significant effect only on fruit number per plant. Means comparison indicated that fruit number, fruit weight per plant and fruit yield in first year were 31.1, 21.3 and 20.1 percent higher than second year, respectively. The highest and the lowest fruit number and fruit weight per plant obtained on 40 cm and 20 cm, respectively. The maximum yield with 16.2 percent was observed in 30 cm space treatment compared to 40 cm which had the lowest rate on those traits. The maximum fruit number and fruit weight per plant obtained in the first year and 40 cm planting space while the minimum number obtained in the second year and 20 cm planting space,. The fruit harvested at several times had 9.9 and 9.6 percent higher than fruit weight per plant and yield respectively, compared to harvested method at once. The maximum and minimum of fruit number per plant achieved in the first year and several time harvesting also in the second year and harvested method at once, respectively with 45.5 percent difference. Qualitative traits Analysis of variance revealed that only year had significant effect on brix and pH. Means comparison showed that pH had 9.3 percent superiority in the first year compared to the second year while brix was 25.2 percent lower in the first year compare to the second year. Labor working time Analysis of variance showed that planting space, harvesting method and their interaction had significant effect on this labor time. Means comparison illustrated that the maximum labor time with 10.5 percent difference were observed in 20 cm planting space treatment compared to 40 cm which had the lowest rate on this trait. The fruit harvested multiple times method needed 127.1 percent more labor compared to harvested method at once. The highest and the lowest labor consumption with 151.6 percent difference, were observed in 30 cm and 20 cm respectively. In tomato production increasing and decreasing of harvest’s expenses, increasing within row space from 20 to 30 cm and one-time harvesting method, had a very important role.