Growth, development, yield and quality of china squash fruits depending on plants layout schemes

Abstract

The article provides the study results on growing Dolia variety of China squash (Cuсurbita moschata Duch. Ex Poir.) by different plant layout schemes. Effect of thickening and thinning of plants on the vegetation season length, productivity and quality of China squash are described.

The aim and tasks of the study. To investigate the effects of plant layout schemes on plant growth, development and yield of China squash.

Material and methods.  The study was conducted in the experimental field of Department of Horticulture of a separated subdivision of NULES of Ukraine ―Agronomic Research Station. Dolia variety (Cucurbita moschata Duch. ex Poir) was studied in 2013-2015. According to ISO 5045: 2008, the control scheme was 1.4 m x 1.4 m (5.1 thousand plants per hectare). Increasing the distance between plants to 1.7-2.0 m, we studied the layout schemes of 1.4 m x 1.7 m and 1.4 m x 2.0 m, and increasing it to 0.8 -1.1 m, we tested the layout schemes of 1.4 m x 1.1 m and 1.4 m x 0.8 m. Herewith, the plant density was 3.5-9.0 thousand plants per hectare. The test was performed according to the methodology of experiments in vegetable and melon cuktivation [11]. The experiment was repeated three times. The account area was 80 m². Plants was cared by the conventional China squash cultivation technology.

Results and discussion. The plant layout of1.4 m x0.8 cm decreased the vegetation period by 4 days when compared to the control (1.4 m x1.4 m). High average fruit weight was recorded for the layout of1.4 m x1.7 m (4.3 kg) and in1.4 m x1.4 m control (4.2 kg); in the variant of1.4 m x0.8 m it was lower (3 kg). The maximum number of fruits (1.9) was achieved in the layout of1.4 m x1.7 m, and its reduction resulted in fewer fruits per plant. High yield (38.2 t/ha) and fruit uniformity (89.8%) were observed in the control scheme of1.4 m x1.4 m. Further increase and decrease in the area resulted in lower yields. The greatest loss was observed in the variant of1.4 m x2.0 m (23.3 t/ha) with the standard fruit yield of 81.1%. Increase in the plant density influenced biochemical parameters of China squash pulp. The lowest amount of nitrates was observed in the layout of 1.4 x0.8 m (106.9 mg/kg). In all the variants, the nitrate content did not exceed the maximum permissible level (200 mg/kg).

Conclusions. In the plant layout of1.4 m x0.8 m, China squash demonstrated shortening of the period of fruit ripening start by 4 days when compared to the control of1.4 m x1.4 m. The highest average fruit weight was recorded for the layout of1.4 m x1.7 m (4.3 kg). The maximum fruit number (1.9) was achieved in the layout of1.4 m x1.7 m. Further increase and decrease in the area led to a reduction in productivity and the average fruit weight. The highest total yield (38 t/ha) was observed for the plant layout of1.4 m x1.1 m. The highest yield of standard fruits was observed in the control (1.4 x1.4 m), and the lowest – in the variant of1.4 m x 20 m. Increase in the plant density influenced biochemical parameters of squash pulp. The lowest amount of nitrates was observed in the layout of1.4 m x0.8 m - 106.9 mg/kg. In all the variants, the nitrate content did not exceed the maximum permissible level (200 mg/kg).