A 2-year study was conducted to assess sweet corn (Zea mays) susceptibility to mechanical weeding using a rotary hoe at preemergence to six-leaf stages of corn development and at different combinations of stages. Three sweet corn cultivars: early (`Quickie'), mid (`July Gem'), and late season (`Sensor') were seeded at two sowing dates. The experiment was conducted in a weed-free environment. In general, sweet corn could be cultivated with the rotary hoe at least once without yield reduction from preemergence to the six-leaf stage. Cob numbers were reduced and maturity delayed after three or four cultivations with the rotary hoe. The rotary hoe could be an effective tool in controlling weeds in an integrated weed management approach or for organic sweet corn production since it cultivates both within and between the rows. The rotary hoe, which covers a large area in a short time, can be used at later growth stages, extending the time period during which it can be used without damaging the crop and reducing yield.
Maryse L. Leblanc, Daniel C. Cloutier and Katrine A. Stewart
Lanqing Wang, Yinfeng Li, Dehai Liu, Chaohui Zhang, Yuancheng Qi, Yuqian Gao, Jinwen Shen and Liyou Qiu
., 2009 ), and biofuel ( Okamura-Matsui et al., 2003 ). Like most other edible mushrooms, its spawn for cultivation is in solid state, which is composed of manure-grass, sawdust, wood block, branch wood, and grain. Solid spawns are universally used by
Riqing Zhang, Fangde Lv, Fang He, Bixia Xie and Lingdan Wang
Pecan [Carya illinoinensis (Wangenh.) C. Koch], a world-famous nut tree native to North America, was introduced to China in the early 1900s. However, little success had been recorded in terms of its nut production. Based on comparative studies of the geoclimate, soil conditions, and growth and performance of the pecan crop between southeastern U.S. and China, as well as in 12 other countries with successful pecan cultivation, it is feasible to grow pecan in China within the latitudes 25–35°N. In these areas, the summer temperatures range from 25–35°C with lower DIF. The annual precipitation is 500–1500 mm. Further studies using the Dendroclimate Predicative Analysis of water and heat conditions in the U.S. Pecan Belt, which is composed of seven factors, including the annual mean and extreme low temperatures, annual frost-free days, and annual precipitation, concluded that four pecan cultivation regions should be designated in China. These regions were the Favorable Region (I), the Northern and Southern Suitable Regions (IIa, IIb), the Northern and Southern Marginal Regions (IIIa, IIIb), and the Northern and Southern Undesirable Regions (IVa, IVb). The Favorable Region is along both sides of the Yangtze River in-between latitudes 25–35 °N and longitudes 100–122 °E. Some areas with microclimates, such as western Yunnan, nourish several pecan cultivars and have demonstrated a promise of pecan production. The demand for pecan is high in China, and this regionalization of pecan cultivation will ultimately enhance further collaboration on pecan production between horticulturists in China, United States, and other countries. Future research will result in the introduction of much better pecan cultivars to the different cultivated regions in China.
Wan-Yi Yen, Yao-Chien Alex Chang and Yin-Tung Wang
.93 dS·m −1 at the end. The EC of the SM with Phalaenopsis reached 1.44 dS·m −1 and that with Oncidium increased to 1.67 dS·m −1 at the end ( Fig. 4B ). Discussion Drop of pH of SM substrate over time is commonly observed in the cultivation of
Kevin M. Miele, Jason J. Henderson and John C. Inguagiato
turf population with a nonselective herbicide, such as glyphosate ( Bauer et al., 2012 ; Kendrick and Danneberger, 2002 ). Intraseeding into existing stands of creeping bentgrass using only cultivation techniques, such as scalping or hollow
Richard L. Parish
Flame “cultivation” for weed control was developed about 50 years ago. The practice was very popular with Southern cotton farmers through the 1950s and 1960s, but lost favor when petroleum prices rose drastically in the 1970s. There is now a new interest in the practice of flame cultivation as a partial or total replacement for herbicides in vegetable crops. This interest is fueled by three factors: 1) an increasingly negative public perception of herbicides on vegetables, 2) a very limited selection of herbicides labeled for vegetables, and 3) limited efficacy of some of the herbicides that are registered. Flame cultivation, in combination with mechanical cultivation, can replace or supplement herbicides in some vegetable crops. The mode of action of flame cultivation is the bursting of cell walls in the weeds as the weeds are heated by a carefully directed LP gas flame. With most vegetable crops, the crop plants must be protected in some manner. This can be done with a water shield (flat fan water spray), height differential between weeds and crop, physical shield, etc. Much of the early work on flame cultivation of vegetables was done with sweet corn. Work is now underway on flame cultivation of lima beans and southernpeas, where multiple flame cultivations have proven effective at controlling weeds for which no herbicide is available.
Thomas S.C. Li
Echinacea species, a popular medicinal herb throughout the world, have been used by indigenous Americans for hundreds of years as an effective immunostimulant. The cultivated acreage in the United States and Canada is increasing because of the great demand for Echinacea products. Better cultural methods and standardization and quality control of the value-added products are needed to increase the confidence of growers, producers, and consumers in this promising medicinal herb. Echinacea can be propagated from seed, crown division, and root sections. Seed stratification for 4 to 6 weeks at 34 to 40 °F (1 to 4 °C) before planting can improve germination. Echinacea thrives under cultivation in moderately rich and well-drained loam or sandy loam soil with regular irrigation and weed control. Roots are harvested in the fall after 3 to 4 years of cultivation. The best stage to harvest flowers has yet to be determined. Leaves are a source of valuable active ingredients, but no information is available in the literature on leaf harvesting. Active ingredients in Echinacea include polysaccharides, flavonoids, caffeic acid derivatives, essential oils, polyacetylenes, and alkylamides.
Renata L. Solan, Jed B. Colquhoun, Richard A. Rittmeyer and Daniel J. Heider
et al., 2001 ; Love et al., 1995 ), incorporation of green manure ( Boydston and Hang, 1995 ), and cultivation ( Bellinder et al., 2000 ). These techniques aim to reduce energy input while maintaining yields achieved with traditional herbicide
Mary Jo Kelly, Marvin P. Pritts and Robin R. Bellinder
are not ideal for matted-row strawberries, cultivation tools are of great interest. Before the development of synthetic herbicides in the mid-1900s, growers relied on mechanical cultivation as their primary means for controlling weeds. Fifty years
W. Carroll Johnson III, David B. Langston Jr., Daniel D. MacLean, F. Hunt Sanders Jr., Reid L. Torrance and Jerry W. Davis
crop and weed emergence. Mechanical weed control (also called physical weed control) using cultivation is among the most reliable methods of weed control in organic crops, including onion ( Ascard and Fogelberg, 2008 ). While there is no standardized