Effects Of Temperature And Photoperiod On Spinach Bolting

Spinach (Spinacia oleralea L.) origins from Asia west of Iran (ancient name of Persia), has more than two thousands years of cultural history, it is the most important green vegetables. Resistance to cold and compatibility of Spinach are strong. The vegetal period is short, can multi-stubble cultivation within one year. Spinach is the important green vegetable during the spring, the fall, the winter three seasons. Spinach includes the rich nutrition, but the spinach does not enduring high temperature, easy to bolting, after bolting , the nutritional quality decrease, affect their commercial value. Bolting-resistant varieties of spinach abroad generally have higher prices, increased domestic production costs of spinach. So study the factors which affecting it bolting, training bolting-resistant varieties are particularly important. This study use three spinaches which different on bolting , studied the affect of different photoperiod and treatment during low temperature on bolting of spinach. Test results are as follows:1. The affect of bolting during different photoperiod: during long-day treatments, the days of bolting shorten. and the role of long-day promotion of easy bolting of spinach varieties in the trade spinach than in the late bolting varieties appear more obvious and easy bolting spinach varieties under long-day than short day treatment with the next 10 days before bolting, bolting-resistant varieties under no bolting in short days.2. Hours of treatment under different light physiological and biochemical changes: light cycle at different treatments, different characteristics of the three spinach bolting varieties of soluble sugar, soluble protein and free amino acid, proline levels were highest in the bolting early , declined rapidly after bolting, nitrate reductase in the whole process has been an upward trend, indicating that light is by changing some the content and activity of the physiological and biochemical substances of bolting in spinach to control bolt sooner or later.3. The growing point of physiological and biochemical changes through treating germinating spinach seeds by low-temperature vernalization : the process at low temperature vernalization, bolting the two quite different spinach varieties of its growing point of soluble sugar and soluble protein content, POD activity were present first increased and then decreased, and are dealing with the first 10 days reached a peak. The free amino acid content decreased first and then increased. In the low-temperature processing, bolting-resistant varieties of spinach growing point of the nitrate reductase activity increased and then decreased after the rise, easy bolting spinach varieties growing point of the nitrate reductase activity and resistance to bolting varieties on the contrary, it showed up - down - up process.4. Low temperature vernalization on bolting of spinach: spinach seed vernalization by treating of low-temperature germination, the results show that the longer the treatment of vernalization, the spinach bolting,flowering earlier, but to a certain time, the low temperature to promote the role of bolting become small. If the vernalization too long, it will affect the growth of spinach, will not achieve the promotion of the role of the bolting on.5. Interaction of photoperiod and low temperature can contribute to the bolting of spinach and role on late bolting varieties appear more clearly.