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  • Author or Editor: James Lasswell x
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Field studies were conducted June 2, July 27, and October 15, 1988 to determine root concentrations within the dry and wetted soil of trickle-irrigated peach trees (Redglobe variety) in Windthorst fine sandy loam soil. Two “dryland” and four irrigation treatments (based on time of year irrigation initiated and previous irrigation history) were used. A single soil core sample 2.2 cm in diameter and 80 cm deep was taken 50 cm from trickle emitters on each of 8 trees per irrigation treatment and a single sample taken the same distance from the trunk on the “dry” side of the 8 trees in each dryland treatment. Each core was sectioned into 20-cm increments, washed, roots collected, separated (small, feeder roots; large suberized roots), dried and weighed.

Analyses of data for the small, feeder roots showed a significant difference (0.01 level) in root density between treatments, between sample times (each treatment), and with depth (each treatment). Root concentrations were highest in soils that had received irrigation in previous years and also when irrigation was initiated early in the year. Root concentrations were also found to be highest in the top 20 cm of soil regardless of treatment.

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Field studies were conducted June 2, July 27, and October 15, 1988 to determine root concentrations within the dry and wetted soil of trickle-irrigated peach trees (Redglobe variety) in Windthorst fine sandy loam soil. Two “dryland” and four irrigation treatments (based on time of year irrigation initiated and previous irrigation history) were used. A single soil core sample 2.2 cm in diameter and 80 cm deep was taken 50 cm from trickle emitters on each of 8 trees per irrigation treatment and a single sample taken the same distance from the trunk on the “dry” side of the 8 trees in each dryland treatment. Each core was sectioned into 20-cm increments, washed, roots collected, separated (small, feeder roots; large suberized roots), dried and weighed.

Analyses of data for the small, feeder roots showed a significant difference (0.01 level) in root density between treatments, between sample times (each treatment), and with depth (each treatment). Root concentrations were highest in soils that had received irrigation in previous years and also when irrigation was initiated early in the year. Root concentrations were also found to be highest in the top 20 cm of soil regardless of treatment.

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Abstract

‘TAMU Denman’ is a new cultivar of peach [Prunus persica (L.) Batsch] developed by the Texas Agricultural Experiment Station for home and commercial orchards in north and central Texas. ‘TAMU Denman’ is a consistently high-yielding, late-blooming cultivar with heavy bud set. These characteristics facilitate commercial production during years when late freezes reduce production from other varieties. It is named for T.E. Denman, Horticulturist at the Texas Agricultural Experiment Station, Stephenville for 31 years.

Open Access

Abstract

Mature peach trees [Prunus persica (L.) Batsch] grown in weighing lysi-meters were subjected to soil moisture stress. Evapotranspiration (ET) was not affected by rapid changes in soil moisture until soil matric potential reached -1500 kPa. When the trees reached permanent wilt, there was a sharp decline in water use.

Open Access

A computer model was used to predict irrigation rates and numbers of emitters or microsprayers required to trickle irrigate Redskin/Nemaguard peach trees. Irrigation rates were 0, 50%, and 100% of the predicted requirement based on a crop coefficient of 50, 80, 100, 80, and 50 percent of pan evaporation for the tree's canopy area for May, June, July, August and Sept. respectively. Full irrigation (100% of predicted) was applied through 6, 8L/hr emitters or one 48L/hr microsprayer. Half the predicted rate was applied through 6, 4L/hr emitters or 1 24L/hr microsprayer. Control trees received no supplemental irrigation. Microsprayers height was adjusted to wet a surface area comparable to the 6 emitters. There was no significant difference in fruit size or yield based on emitter vs microsprayers, but fruit size and total yield was increased in direct proportion to irrigation rate. There was no treatment effect on tree pruning weights. Moisture measurements indicated that trees de-watered the soil efficiently enough that water never moved below the 30 cm level in spite of the fact that up to 260 liters per tree per day were applied in mid-summer.

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