Ethanol and acetaldehyde production by cotton seeds subjected to anoxic stress imposed by CO₂ or N₂ gas was quantified during the imbibition phase. Fermentation capacity was low in dry seeds and quickly increased during the first few hours of imbibition. In hydrated seeds, ethanol and acetaldehyde excretion following anoxic stress followed a linear trend in time. Ethanol excretion exceeded that of acetaldehyde by an order of magnitude. Similar rates of production were observed whether anoxic was imposed by either CO₂ or N₂ gas. Excreted ethanol and acetaldehyde were rapidly metabolized following alleviation of anoxic stress.

Leakage of reducing sugars and amino acids during cotton seed imbibition was evaluated as a possible vigor test. Seed samples from a single cotton seed lot were subjected to accelerated aging at 46°C and 100% R.H. for up to 216 hours. Aged seeds were imbibed at optimal and suboptimal temperatures, and the leakage of total reducing sugars and amino acids into the imbibition solution was quantified spectrophotometrically. Leakage of seed reserves was positively correlated with the duration of accelerated aging, in terms of subsequent germination performance at 30°C and of similar quantity at both imbibition temperatures.

A field study was carried out to test the effectiveness of several defoliation treatments on Upland cotton in Pinal County. Three defoliation treatments were utilized. Results showed no significant differences among treatments in terms of percent leaf drop estimates taken seven and 14 days after initial application. Subsequent applications of defoliant materials were made to accomplish satisfactory levels of defoliation prior to harvest.

This test was conducted on the LDS Church Farm in Marana to determine whether ripping after the Uprooter-Shredder-Mulcher (USM) benefits yields. The three treatments were rip furrows only, rip -beds only, and no ripping after the USM. Depth of water penetration was measured after the preplant irrigation; no significant differences were observed between the treatments. Differences in lint yields were not statistically significant, although average lint yields for the ripped treatments were higher.

Cotton growers began cotton harvest earlier in 1987 than during the previous three years, but they fell behind the other years by December first. Rainfall in late October, particularly November 2, slowed harvest and reduced quality of cotton dramatically in some operations.

A preplant application of zinc was made to a short staple cotton field where the soil analysis had shown a zinc concentration of 0.64 ppm. No significant yield response was measured.

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Anoxic -induced fermentation was evaluated as a potential cotton seed vigor test. Seed samples from a single seed lot were subjected to accelerated aging for different durations to create five classes of seeds on the basis of vigor. The ethanol and acetaldehyde excreted from seeds from each class during brief periods of anoxia was quantified by gas-liquid-chromatography. Ethanol and acetaldehyde production during anoxia was negatively correlated with standard germination test results of all seed samples receiving accelerated aging. The fermentation capacity of hydrated cotton seeds remained intact at imbibition temperatures, which significantly reduced radicle growth.

Planting Pima S-6 at 12-day intervals starting April 2 produced more than 70 pounds of lint loss for each delay in planting.

Double cropping barley and cotton, using a system of controlled traffic tillage, was compared to conventionally tilled, full-season cotton. In this test, the yields of the barley and late planted cotton were too low to be competitive with the full season cotton.