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This study aimed to evaluate the effects of liming on soil fertility, growth, nutrition and production of red pitaya (Hylocereus monacanthus) plants cultivated in pot. The experiment was conducted in blocks, with five doses of limestone (0.0; 0.6; 1.2; 1.8; and 2.5 t ha−1) and four replicates. Corrective doses were established to achieve base saturation of 20 to 70%. Liming increased soil pH (4.5 to 6.7), Ca concentration (5.36 to 20.11 mmolc dm−3), Mg concentration (4.36 to 16.53 mmolc dm−3) and base saturation (23.69 to 72.61%) and reduced potential acidity (37.39 to 15.41 mmolc dm−3). Liming reduces nitrogen concentration and increased phosphorus, calcium and sulfur concentrations in the cladodes. There was an increase in phosphorus concentration and decrease in boron and iron concentrations in fruit peel according to the increase in limestone doses; in the pulp, there was an increase in boron concentration and decrease in iron and zinc concentrations, from the lowest to the highest dose of limestone. Based on the principal component analysis, the limestone dose of 1.8 t ha−1 increased base saturation to 59%, providing favorable chemical conditions for the growth and productivity of red pitaya. [ABSTRACT FROM AUTHOR]

Citrus cultures have a fundamental importance to the Brazilian economy; certain aspects such as plant nutrition, yield, and fruit quality are vital for the citrus industry sustainability. The present study evaluated the nutritional status of manganese in adult Pear orange trees using different lime rates topically applied to the soil. The direct evaluation of lime rates effects on leaf manganese (Mn) levels revealed a decrease of the nutrient correlated to its increased, as well as passage of time between application and measurement. Foliar sampling 30 months after surface lime application evidenced a high correlation of foliar manganese levels with soil base saturation of 10-20 cm. Leaf manganese levels which showed a great probability of high productivity were between 33 and 70 mg kg-1. [ABSTRACT FROM AUTHOR]

The experiment considered Vitis vinifera L. cv. “Pinot blanc” clone VCR5 grafted on a lime-susceptible (3309 C) and a lime-tolerant (41 B) hybrid rootstock and grown in 45 L pots of a calcareous and a non-calcareous soil. Each treatment included plants bearing clusters and plants without clusters; in the latter case the bunches were removed 15 days before blooming. During the third growth year, shoot length, leaf chlorophyll (Chl), and mineral element concentrations were recorded. At the end of the growing cycle the grapevines were divided into leaves, shoots, berries, cluster stems, trunk, roots, and dry matter and mineral element composition per organ were analyzed. The 41 B rootstock showed its lime-tolerance by exhibiting little reduction of shoot length when grown in the calcareous soil as compared to the non-calcareous one, while 3309 C growing in the calcareous soil induced a dramatic shoot length reduction. The rootstock also affected the leaf chl concentration according to the known degree of lime-tolerance/susceptibility: “Pinot blanc” grafted on 3309 C and growing on the calcareous soil showed chlorotic leaves while the plants grafted on 41 B had green leaves; cluster removal did not affect leaf chl. The fruit load (expressed as berry dry matter) was strongly affected by the soil and the rootstock; in the calcareous soil 41 B rootstock produced twice as high cluster dry matter than did 3309 C. A higher macronutrient uptake for the plants growing under lime-stress conditions was affected by 41 B rootstock. Cluster removal in plants grown on calcareous soil produced different effects, as follows: in the case of 41 B rootstock, a redistribution of photosynthate to other sinks like shoot tip and roots occurred, while in the case of 3309 C only the roots benefited. Under lime-stress condition the plants grafted on 41 B took up more iron (recorded as total amount in the leaves) than did those grafted on 3309 C. [ABSTRACT FROM AUTHOR]

For economical reasons, cucumber (Cucumis sativus L.) may be grown as a double crop after tomato (Lycopersicon esculentum Mill.). In this production system, plant nutrition may be limited for the second crop due to pH change or insufficient levels of calcium or magnesium. The objective of this 2-year field study was to compare the effects of selected liming materials on yield and grade distribution, and soil available nutrients of a tomato/cucumber double crop produced with plasticulture. Liming materials were compared to a control and a CaSO4 treatment based on the same neutralizing value as standard agricultural limestone. Supplemental N fertilization was provided by weekly injections at a rate of 7 kg/ha/week from ammonium nitrate (NH4NO3) or calcium nitrate [Ca(NO3)2]. Each year, soil samples were collected at the beginning of the study and after each crop to determine nutrient availability. All liming materials raised soil pH in 1998 and 1999 over the unlimed control, though not to the target level for tomato and cucumber production (pH 6.5). Throughout the study, agricultural limestone, a high CaO-containing blend (calcitic blend) and a CaO/MgO (dolomitic blend), resulted in greater fruit weights compared to the control and CaSO4. These materials, along with quick lime (CaO), provided higher levels of soil Ca and Mg available for plant growth. However, it was found that current recommendations for potassium (K), regardless of liming source, were not adequate for optimal soil reserves and yields in this tomato/cucumber cropping system. Ammonium nitrate as a source of N for fertilization was as effective as Ca(NO3)2. [ABSTRACT FROM AUTHOR]