INTEGRATED WATER, NUTRIENT AND PEST MANAGEMENT STRATEGIES FOR SUBTROPICAL CROPS
Title: Watermelon transplanted by chisel, strip-tillage, and bedding methods produce similar yield and quality
Submitted to: Subtropical Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 9, 2011
Publication Date: August 23, 2011
Citation: Makus, D.J. 2011. Watermelon transplanted by chisel, strip-tillage, and bedding methods produce similar yield and quality. Subtropical Plant Science. 63:7-13.
Interpretive Summary: Constraints to watermelon production in south Texas (Lat. 26º26’N) typically include wind (-blown soil erosion and vine wilting/movement), intense sunlight, and timely water application. In order to evaluate the impact of planting into high surface residue soil, watermelon seedlings were transplanted by two relatively low disruptive methods, chiseling and strip-tilling, and by the standard soil disruptive method of discing/roto-tilling and bedding. Transplanting watermelon seedlings into a high surface mulch, either by chiseling or strip-tilling, resulted in watermelon yields and quality comparable to the standard field preparation methods which require higher energy inputs of fuel and equipment (capital) to form transplant beds. There were no differences in water use, but upper soil temperatures were reduced by not disturbing the mulch in the chisel and strip-tilled plots compared to the bare ground beds. The seeded ‘Jamboree’ cultivar responded best to the presence of high mulch as opposed to bare ground beds by producing a higher percentage of marketable fruits. The smaller-sized seedless ‘Tri-X 313’ cultivar produced more marketable fruit than did ‘Jamboree’, probably due to its ability not to split when high rainfall events occurred late in the growing season.
Watermelon plants grown in semi-arid, subtropical south Texas (Lat. 26° N) are subject to wind and high solar loads. In an effort to provide an environment that would reduce wind-related sand blasting, early transplant desiccation, and vine damage and reduced soil temperatures, watermelon seedlings were transplanted into chisel- and strip-tilled high surface residue (14 t/ha) Raymondville silt-loam soil and compared to the standard method of plowing and bedding. A diploid, ‘Jamboree’, and a triploid ‘Tri-X 313’ watermelon were used as sub-plots in a transplant establishment (main-plots) experiment with four replications. Maintaining high soil residue reduced average daily soil temperatures in the chisel and strip-tilled establishment plots at 5 (P=0.03), 10 (P=0.20), and 30 cm (P=0.01) depths compared to bedded melons. Daily maximum surface temperatures (unreplicated), measured by IR thermometry, were lowest in the bedded plots, suggesting that soil cooling by water loss might be the reason for the lower temperatures. However, seasonal moisture at 30 cm was influenced only by date and not by transplant method. Rainfall for the experimental period was unseasonably high (52% of ET). Plant establishment method did not influence average fruit weight, marketable fruit weight, or marketable fruit number, but planting into high residue soil increased both marketable yield (%) and marketable fruit (%) with ‘Jamboree’ showing the greatest response to a high residue environment. Fruit quality attributes were not affected by plant establishment method, but ‘Tri-X 313’ soluble solids (%) was higher than that of ‘Jamboree’ (12.0 vs. 11.5 %). Cultivars did differ in fruit weight, marketable fruit, and marketable yield (%), and marketable fruit number (%).