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Compost increases nutrient availability, cation exchange capacity, and micronutrients in the soil. In urban areas, yard waste consisting of grass clippings, leaves, and woody materials can be composted. The purpose of this study was to compare the effects of soil-composted municipal sludge and soil-composted yard waste mixtures on strawberry plants grown in the greenhouse. Earliglow strawberry plants were planted in pots containing a soil mix of 0%, 10%, 20%, or 40% by volume of composted municipal sludge or composted yard waste. Plants were grown in the greenhouse with supplemental lighting. Soil-compost mixes having greater the 90 mhos of soluble salts were detrimental to the plants; plant survival was reduced by 80% in the 40% composted sludge–soil mix within 2 weeks after transplanting. Plants survived and grew in all other treatments. Composted yard waste at 20% to 40% by volume increased leaf K and B, but decreased P, Ca, and Mg.
We investigated the response of staminate and pistillate floral components of Prime-Jan™ and Prime-Jim™ primocane-fruiting blackberry (Rubus L. subgenus Rubus Watson) to three different growth chamber temperature regimes, 35.0/23.9 °C (HT), 29.4/18.3 °C (MT), and 23.9/12.8 °C (LT). Temperature was negatively related to flower size and morphological abnormalities in floral structures were evident in 41% and 98% of the MT- and HT-grown plants, respectively. The viability (stainability) of pollen from LT- and MT-grown Prime-Jan™ flowers exceeded 70%; that of Prime-Jim™ pollen was significantly reduced (<40%) by the MT regime. Pollen in-vitro germinability was negatively influenced by temperature but was unaffected by cultivar. LT-grown pollen held at 23.9 °C retained 63% of its original germinability over a 32-hour period; the germinability of LT-grown pollen held at 35.0 °C was decreased by 97% from its original level after 16 hours. Virtually all flowers cultured under HT conditions were male-sterile, exhibiting structural and/or sporogenous class abnormalities including petaloidy, malformation of tapetal cells, and microspores or failure of dehiscence. The duration of stigma receptivity, pistil density, and drupelet set were also negatively influenced by increasing temperature; values for these parameters of floral competency among control plants were reduced by 51%, 39%, and 76%, respectively, in flowers cultured under HT conditions. Herein, flowering and fruiting parameters and presumably the yield potential of Prime-Jan™ and Prime-Jim™ were adversely affected by increased temperature. However, assessment of their adaptative response to heat stress under field conditions awaits experimentation.
We investigated the responses of staminate and pistillate floral components of Prime-Jan and Prime-Jim primocane-fruiting blackberry (Rubus L. subgenus Rubus Watson) to three different growth chamber temperature regimens, 35.0/23.9 °C (HT), 29.4/18.3 °C (MT), and 23.9/12.8 °C (LT). Temperature was negatively related to flower size, and morphologically abnormal floral structures were evident in 41% and 98% of the MT- and HT-grown plants, respectively. Anthers of LT- and MT-grown plants dehisced. The viability of pollen (as deduced through staining) from Prime-Jan grown at LT or MT exceeded 70%, whereas that of Prime-Jim pollen was significantly reduced (<40%) by the MT regimen. In vitro pollen germinability (typically <50%) was negatively influenced by temperature but was unaffected by cultivar. Pollen useful life was diminished under HT conditions; LT-grown pollen held at 23.9 °C retained 63% of its original germinability over a 32-h period, while the germinability of that held at 35.0 °C for 16 hours decreased by 97%. Virtually all flowers cultured under HT conditions were male sterile, exhibiting structural or sporogenous class abnormalities including petaloidy and malformation of tapetal cells or microspores; HT anthers that were present, failed to dehisce. Stigma receptivity, pistil density, and drupelet set were also negatively influenced by increased temperature; values for these parameters of floral competency among control plants were reduced by 51%, 39%, and 76%, respectively, in flowers cultured under HT conditions. In this study, flowering and fruiting parameters, and presumably the yield potential of Prime-Jan and Prime-Jim, were adversely affected by increased temperature. However, their adaptive response to heat stress under field conditions awaits assessment.
Abstract
Carbofuran (2,3-dihydro-2,2-dimethyl-7 benzofuranyl methylcarbamate) at 5.7 and 11.1 kg/ha reduced soil populations of lesion (Paratylenchus penetrans, Filipjev & Shuurmans Stekhoven), pin (Paratylenchus sp. Cobb), and lance (Hoplolaimus galeatus, Cobb, Filipjeu & Schuurmans Stekhoven) nematodes. The highest rates of granular and flowable carbofuran were phytotoxic on peach [Prunus persica (L.) Batsch] planted just prior to treatment. In a subsequent experiment in soil previously planted to peach (old soil) or not previously planted to peach (new soil), trickle irrigation alone reduced dagger (Xiphinema americanum, Cobb) and lesion nematode populations. Carbofuran plus trickle irrigation reduced the dagger and lesion nematode populations and had the highest rate of tree growth in the old soil. Granular phenamiphos (ethyl-3-methyl-4-(methylthio) phenyl (1-methylethyl) phosphoridate) either alone or in combination with trickle irrigation reduced the stunt (Tylenchorhynchus claytoni, Steiner) nematode population. However, when phenamiphos was applied alone, tree growth was equal to the control in old soil but less than the control in new soil.
Abstract
An internal rate of return technique was used to analyze and compare 4 orchard densities producing ‘Golden Delicious’ apples (Malus domestica Borkh.) on a “typical” Pennsylvania fruit farm with a fresh market system and both hand and mechanical harvested processing systems. Medium and high density systems had similar rates of return both of which were higher than the low density systems. The high density system had higher net returns per unit area than the medium density systems.