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The study aimed to analyze the effect of seed treatment with micronutrients on the growth of rainfed rice plants. Treatments consisted in the absence of micronutrient application, single applications or a combination of five micronutrients applied to seeds: compound Zinc + Molybdenum (Mo 2.3, Zn 3.5 % w/v) in a dose of 2 mL kg-1 seed; Copper + Molybdenum + Zinc + Manganese (6.7 Cu, 3.2 Mo, 15 Zn; 9.4% Mn w/v) at a dose of 3 mL kg-1 seed; Zinc (100% Zn p/v) at a dose of 2 mL kg-1 seed, Manganese (50% Mn w/v) at a dose of 2ml kg-1 seed, Boron (3% B w/v) at a dose of 3 mL kg-1. Plants were collected at, three, seven and eleven days after emergence with readings of leaf area and estimates for dry weight of shoots and roots. From these data calculations were derived for the total plant dry mass, shoot/root ratio, ratio of leaf area to leaf mass and the specific leaf area. The compound mixture of Cu + Mo + Zn + Mn provided the highest seedling dry matter accumulation and highest leaf area, while single zinc applications stimulated the accumulation of root dry mass. Seed treatment with micronutrients provides better performance for the initial growth in rainfed rice plants.

Fruit and stem water potentials of tomato plants were measured continuously for several days using automated psychometers. A linear voltage displacement transducer was used to simultaneously measure diameter changes on an adjacent fruit. a strong correlation was observed between the water potential gradient of the fruit and stem, and changes in fruit diameter. Fruit diameter increased when the apoplasmic water potential gradient favoured solution flow into the fruit and fruit shrinkage occurred only when the water potential gradient was inverted. Based on our data and other published data (Ehret & Ho 1986; Lee 1989a) on phloem transport in tomato, we have concluded that low stem water potentials have an immediate and direct effect on phloem turgor; reducing the driving force for sap flow into the fruit. Since fruit water potential remained relatively constant, the diurnal variation in stem water potential was sufficient to account for the correlation with changes in fruit diameter. There are consequently with respect to predicting the accumulation of dry matter in tomato fruit. [ABSTRACT FROM AUTHOR]