Cotton Row Research Articles

Strip Cropping: A Potential IPM Tool for Reducing Whitefly, Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) Infestations in Cassava

Insect pests and diseases are a major limiting factor to cassava production in Africa. The cassava mosaic virus disease (CMVD), caused by cassava mosaic geminiviruses (CMGs) (Geminiviridae: Begomovirus) and transmitted by whitefly, Bemisia tabaci Gennadius , threatens the production of the crop in Africa, causing an estimated annual yield loss of over 1.5 billion US dollars. A 6-month field experiments were conducted to explore the potential of using strip cropping to reduce whitefly infestations in cassava, Manihot esculenta Crantz (Euphorbiaceae). Five rows each of cassava, Jatropha and cotton were grown around a 10-row (1 m row width) × 25 m cassava plots in a randomized complete block design. At weekly intervals, the levels of whiteflies infestations (number of eggs, nymphs and adults) per plot were determined. A significantly lower numbers of immature (egg and nymph) and adult Bemisia tabaci were found in cassava plots surrounded on all sides by five rows of both cotton and Jatropha curcas, clearly demonstrating the potential of strip cropping as a management option for the suppression of Bemisia tabaci populations.

Weed Management in Single- vs. Twin-Row Cotton (Gossypium hirsutum)

Research was conducted to determine the effect of planting pattern, plant density, and levels of weed management intensity on intercepted photosynthetically active radiation (IPAR), weed control, and cotton lint yield in glyphosate-resistant cotton. Twin-row planting pattern canopy IPAR was 55% 7 wk after emergence (WAE) and 76% 9 WAE compared to 48% for single-row planting pattern 7 WAE and 59% 9 WAE. Regardless of cotton density, row spacing, or weed management intensity, control of browntop millet and Florida beggarweed was at least 88% 18 WAE. Benghal dayflower, sicklepod, and smallflower morningglory control was greater in twin-rows compared to single-rows at a cotton density of 7 plants m−2. Control of Benghal dayflower and sicklepod increased when cotton density increased at low weed management intensities; however, cotton density had no effect on weed control at higher levels of weed management input. At a cotton plant density of 7 plants m−2, twin-row cotton yielded 220 kg ha−1more than the single-row planting pattern. Data indicates twin-row cotton production is feasible and that control of various weeds was better in twin-row than single-row pattern at lower cotton density and weed management intensity.

Row spacing, tillage system, and herbicide technology affects cotton plant growth and yield

Cotton ( Gossypium hirsutum L.) producers are faced with numerous production choices including cotton varieties, herbicide technology, tillage systems, and row spacing. A study was conducted to compare cotton production across conventional, glyphosate-tolerant, and glufosinate-tolerant varieties in both conventional and conservation tillage systems for standard row (102 cm) and narrow row (38 cm) cotton planting patterns. The experiment was conducted during the 2004–2006 growing seasons at the Field Crops Unit, E.V. Smith Research Center, near Shorter, AL in long-term tillage plots. Data collection included plant populations within row spacings, plant biomass and height at 1st square, mid-bloom, and lint yields. Plant biomass measured at 1st square and mid-bloom was affected by growing season with 38 cm cotton plant biomass averaging 34% greater in 2004 and 2005, however, the effect of tillage system was contradictory within the growing season. Mid-bloom plant biomass also varied across growing seasons with 21% more plant biomass recorded in 38 cm rows averaged across all three growing seasons. Plant heights were shorter for 38 cm cotton compared to 102 cm cotton, regardless of growth stage or tillage system. No differences in cotton development were observed across varieties. Cotton planted in 38 cm rows yielded equivalent to 102 cm cotton during two of the three experimental years and was superior to 102 cm cotton the remaining year, which corresponded to the best growing season observed during the experimental period. These results indicate that 38 cm cotton production can produce yields that are at least equivalent to standard 102 cm cotton, despite differences in plant development. The productivity of a narrow row cotton production system may be attractive to some growers, but economic evaluations are required to determine if the system is profitable on a large scale based on equivalent or marginal lint yield increases.

Development of a synthetic plant volatile‐based attracticide for female noctuid moths. III. Insecticides for adult Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

AbstractWe investigated the efficacy of insecticides combined with a plant volatile‐based attractant for Helicoverpa armigera moths, under laboratory and field conditions. In the laboratory, 16 insecticides were assessed by the level of mortality and time to incapacitate and kill moths. The proboscis extension reflex technique was used for dosing moths. The pyrethroids, bifenthrin (only when synergised by the addition of piperonyl butoxide (PBO) but not without it) and cyfluthrin (with or without PBO), endosulfan, the carbamates methomyl and thiodicarb, and spinosad killed all moths tested at rates equivalent to, or less than, those which would be applied in cover sprays targeting larvae. The shortest time to moth incapacitation and death was observed with methomyl and thiodicarb. Spinosad produced very high mortality but moths took much longer to die. The two pyrethroids gave relatively slow kills, as did endosulfan. In a field trial, four insecticides were combined with the attractant and dead moths were collected daily from 1 to 4 days after application of the attracticide on 50 m rows of cotton. Significantly more dead moths (H. armigera, H. punctigera and other noctuids) were found near the rows treated with attracticide containing methomyl compared with spinosad, fipronil and deltamethrin. For determining the impact of attracticides by recovering dead moths, quick acting insecticides are required to prevent moths flying away from the treated area to locations where they cannot be found. Methomyl and thiodicarb are suitable for this, but other insecticides especially spinosad could be used where quick action is not needed. Large numbers of moths were killed in the field trial, suggesting that attracticides for female Helicoverpa spp. moths could have significant impacts on local populations of these pests.

Pest Incidence and Yield as Influenced by Intercropping Unconventional Greenmanures in Cotton

Field experiments were conducted at Agricultural Research Station, Bhavanisagar, Tamil Nadu, India to find out the effect of Intercropping unconventional greenmanures on pest incidence and yield of cotton during the year 2004 -2005 in well drained sandy clay loam soil. Four cropping systems viz, sole cotton, cotton + marigold (Tagetus erecta L.), cotton + sesamum (Sesamum indicum L.) and cotton + sunnhemp (Crotalaria juncea L.) were tested (Factor A) in single and double rows (Factor B) incorporating them on 30 and 40 DAS (Factor C). The results revealed that intercropping with marigold in two rows in between cotton rows and incorporating it on 30 DAS had contributed ultimately to less incidence of pests and more kapas and lint yield of cotton securing higher yield advantage in both summer and winter crops Sunnhemp and sesamum had moderate and low effects, respectively on pest incidence.

Sampling Stink Bugs (Hemiptera: Pentatomidae) for Population Estimation and Pest Management in Southeastern Cotton Production

Stink bugs (Hemiptera: Pentatomidae) were sampled in commercial cotton, Gossypium hirsutum L., fields in 2007 and 2008 in South Carolina and Georgia. The main species collected with the beat cloth and sweep net methods were green stink bug, Acrosternum hilare (Say) (63 and 57%, respectively); brown stink bug, Euschistus servus (Say) (23 and 18%, respectively); and southern green stink bug, Nezara viridula (L.) (14 and 22%, respectively). Average stink bug densities were 0.145 +/- 0.010 (mean +/- SEM) for adults and 0.250 +/- 0.027 for nymphs per 3.7 m of row by using the beat cloth method. Average stink bug densities were 0.291 +/- 0.016 for all adults and 0.137 +/- 0.018 for all nymphs per 50 sweeps. A density of two southern green stink bugs per 3.7 m of row by using the beat cloth method required 43 samples (reliability or precision, Dx = 0.3) for population estimation, whereas 88 samples were necessary for a density of two southern green stink bugs per 50 sweeps. At low densities, the sweep net was a more cost-reliable sampling method for all species and life stages. For adult stink bugs, the beat cloth method became more reliable at densities of 1.0, 3.2, and 5.8 stink bugs per 3.7 m of cotton row for southern green stink bug, brown stink bug, and green stink bug, respectively. Sequential sampling consistently reduced sample size for all insects compared with a fixed sampling plan.

Enhancement of refuges for Helicoverpa armigera (Lepidoptera: Noctuidae) used in the resistance management plan for cotton (Gossypium hirsutum L.) containing Bollgard II® traits

Helicoverpa armigera (Hubner) egg densities were sampled across interfaces between cotton containing Bollgard II® traits and pigeonpea or unsprayed non-transgenic cotton refuges to determine the effectiveness of the refuge crops for Bollgard II® resistance management plans (RMPs) against H. armigera. Additionally, a commercially available moth-attraction technology (Magnet®) was included at interfaces with both refuge crops to determine whether the use of such an attractant technology enhances the effectiveness of the refuges. Where the refuge crop was unsprayed non-transgenic cotton, there was no consistent change in the egg-density profile across the interface, suggesting that the Helicoverpa moths were not detecting and responding to the transition from Bollgard II® to non-transgenic cotton. However wherever Magnet was applied, there was a consistent increase in egg density on or near the Magnet-treated cotton rows. This suggests that moth-attraction technology has potential to increase the efficiency of non-transgenic cotton refuges by increasing oviposition there so that the refuge produces more individuals unselected for Bt trait resistance. However, it is not yet known how best to deploy insect-attraction technology in non-transgenic cotton refuges. Pigeonpea was a very attractive refuge crop, with Helicoverpa egg densities an order of a magnitude higher than the adjacent Bollgard II® crop and with no spillover of this increased oviposition into cotton. Application of moth attractant to the edge of the pigeonpea refuge did not alter the egg-density profile across the crop interface, suggesting that the combination of moth-attraction technology with pigeonpea refuges would not increase the effectiveness of the refuge. These studies identify avenues for improving the effectiveness of refuge crops for the management of Bt resistance in H. armigera.

The Economic Benefit of Improving the Proximity of Tillage and Planting Operations in Cotton Production with Automatic Steering

Producers in the Coastal Plain of the southeastern United States manage soil compaction in conservation tillage systems by in-row subsoiling prior to planting. However, planting directly over the loosened zone of soil can be difficult in high-residue conservation tillage systems where cover crop production is maximized. Tractors with automatic steering capability could assist with placement of deep tillage in close proximity to planting operations, but little is known about the accuracy necessary to maximize rooting development, reduce succeeding soil compaction, and optimize crop production. An experiment was conducted in south-central Alabama to evaluate the distance the cotton row can be from deep tillage and still affect cotton yield and economic performance. Results showed as distance between the planted row and tillage pass increased, seed cotton yields were reduced by as much as 24% to 52% and net revenues from cotton production by as much as 38% to 83%. An economic analysis of on-farm adoption showed that auto-guidance systems with accuracy of less than 2.5 cm may be the most profitable for larger farms, while systems with less than 10 cm accuracy may provide a better economic alternative for smaller farms.

Influence of planting date on the relationship between populations of Frankliniella flower thrips and predatory bug Orius niger in cotton

The influence of three planting dates [mid-March (early-planted), 15 April–15 May (normal-or timely planted) and mid-June (late-planted)] of cotton variety SG 125 on the relationship between populations of Frankliniella flower thrips (Thysanoptera: Thripidae) and the predatory bug, Orius niger (Wolff) (Hemiptera: Anthocoridae) were investigated in Adana province in the Eastern Mediterranean region of Turkey in 2003 and 2004. To facilitate emergences of cotton seedlings in early-plantings, cotton rows were mulched after sowing. Adult Frankliniella occidentalis (Pergande) dominated the thrips populations in flowers and colonized the flowers rapidly with high numbers in early-and normal-planted cotton, while adult F. intonsa (Trybom) were significantly more abundant on flowers in late-planted cotton (P ≤ 0.05). The significantly higher but short-lasted larval developments were detected only in late-planted cotton in both years (P ≤ 0.05). Although some scarring and silvering damage on leaves and bolls caused by larval feedings occurred in the late-planted cotton, Frankliniella flower thrips did not have any detrimental effect on plant developments and cotton yields in any of the plantings. Early- and mulch-planted cotton produced significantly higher numbers of fruiting parts and also cotton yield, followed by normal-planted cotton (P ≤ 0.05). We commented that the lower cotton yield in late-planted cotton were due to physiologically caused abscissions of the fruiting parts under unfavourable climatic conditions. O. niger was an effective predatory insect of Frankliniella thrips in the flowers especially in normal-planted cotton, as it was detected in significantly high numbers and thrips-to-predator ratios were lower. It is suggested that early planting of cotton in March could be a good cultural practice in the Mediterranean region.

Temperature-mediated developmental delay may limit yield of cotton in relay intercrops with wheat

In the Yellow River valley of China, more then 1.4 million ha of cotton are grown as relay intercrops with wheat. Cotton is sown in April when winter wheat is already in the reproductive phase; thus, a wheat crop with a fully developed canopy will compete for resources with cotton plants in the seedling stage. Yields of cotton are lower in relay intercropping systems than in a monocrop, but the aggregate yield of the cotton–wheat system is greater than of monocultures of the component crops. We study the hypothesis that the lower yield of intercropped cotton is a consequence of delayed development and fruit formation of the cotton as a result of a lowered temperature experienced by seedlings in the intercrop, compared to monoculture, due to shading by wheat. Field experiments were conducted in 3 subsequent years in Anyang, Henan, China. Wheat and cotton were grown as monocrops and as strip intercrops. Four intercrop layouts were investigated, differing in number of wheat and cotton rows in a strip: 3:1, 3:2, 4:2 and 6:2. Developmental stage of the cotton was recorded at regular intervals during the growing cycle while air and soil temperatures were measured with thermocouples at several soil depths and cross-row positions in the canopy. Temperatures at and near the soil surface were substantially (on average 3 °C) lower in intercrops than in monoculture, especially on sunny days, thus lowering the rate of temperature accumulation of cotton seedlings in intercrops, compared to those in monocultures. Cotton in intercrops showed a pronounced delay in early development, e.g. attainment of the squaring stage, compared to monocrops. The period from planting to first square, expressed in thermal time (TT), lasted 531 °C d in cotton monoculture and 638–670 °C d in intercrops. There were no significant differences in developmental delay between different intercropping patterns. The formation of fruits in intercrops lagged behind by 9–15 d, compared to monoculture, while the number of fruit nodes per plant, averaged over 3 years, was reduced from 30.3 in monocrops to 19.9 in intercrops. The later formation of fruits thus results in a reduction in fruit number and also in a reduction in average age of the fruits, limiting their growth and the sink capacity of the plant as a whole. A plastic film cover increased temperatures in a 3:2 intercrop at the soil surface by 1.9 °C and at 5 cm soil depth by 2.7 °C, thus restoring the thermal conditions to levels common in monoculture. A cover with straw, however, decreased the temperature at the soil surface by 2.9 °C and at 5 cm depth by 1.3 °C. We conclude that the thermal climate in wheat–cotton intercrops is suboptimal for the cotton seedlings. The resulting delay in development of cotton culminates in a lower reproductive capacity and sink capacity. In combination with a reduced source strength, due to later and reduced canopy development in intercropped cotton, these effects result in a lint yield that is substantially lower than in monoculture cotton. This constraint can be ameliorated by measures that improve light capture and heat loading by the cotton, e.g. planting a semi-dwarf wheat or cultivation of cotton on ridges, or application of a plastic film mulch in the cotton seed bed. Early maturing cotton cultivars are at an advantage in intercropping systems.

Effect of Row Proximity to In-Row Subsoiled Zones on Cotton Productivity

Producers in the Coastal Plain of the southeastern United States manage soil compaction in conservation tillage systems by in-row subsoiling prior to planting. However, planting directly over the loosened zone of soil can be difficult in high-residue conservation tillage systems where cover crop production is maximized, because the loosened soil is often covered by the large amounts of cover crop residue. Tractors equipped with guidance systems could assist with placement of in-row subsoiling and planting operations, but little is known about the accuracy necessary to maximize rooting development, reduce succeeding soil compaction, and optimize crop yield. An experiment was conducted in south-central Alabama to determine the maximum distance in-row subsoiling performed by three different implements could be from the cotton row without reducing cotton growth and increasing soil compaction. Results showed that if the cotton row was within 5.1 cm of in-row subsoiling, the relative seed cotton yield is 44% greater than a corresponding no-subsoiling treatment. No significant differences were found between the three in-row subsoiling implements used in the experiment. Recommendations resulting from this experiment indicate that to maximize crop yields and minimize soil compaction in the row, the subsoiled zone should be kept within 5 cm of the row.

Growth, yield and quality of wheat and cotton in relay strip intercropping systems

Intercropping of wheat and cotton is practiced at a large scale in northern China, but the productivity of intercrops, compared to monoculture, and the productivity and growth patterns of different alternative intercropping patterns have not been quantitatively documented. In this study, four typical wheat–cotton intercropping patterns were examined as to their growth and productivity in field experiments over three growing seasons in Anyang, Henan Province, China. The systems varied in the number of wheat and cotton rows in the alternating strips of either crop, and were labeled accordingly as 3:1, 3:2, 4:2 and 6:2. Dry matter accumulation, yield, land equivalence ratio (LER) and lint quality were determined. Grain yield of wheat, averaged over three seasons, ranged from 4600 to 5200 kg ha −1 in intercropping, corresponding to 70–79% of the yield in the monoculture (6550 kg ha −1). The 3:1 system gave the highest wheat yield (79% of monoculture), followed by the 6:2 (73%), 3:2 (70%) and 4:2 (70%) systems. Cotton lint yield, averaged over three seasons, ranged from 590 to 740 kg ha −1 in intercropping, corresponding to 54–69% of the yield in cotton monoculture (1085 kg ha −1). The 3:2 and 4:2 systems gave the highest lint yields (69% and 68% of monoculture, respectively), which was significantly lower than in monoculture but significantly higher than in the 3:1 (58%) and 6:2 (54%) systems. The land equivalent ratio was 1.39 in the 3:1, 3:2 and 4:2 systems, and significantly lower, 1.28, in the 6:2 system. All systems provide a substantial land use advantage. Cotton growth patterns in monocultures and intercrops were characterized by fitting expolinear growth equations to periodic harvest data. Fitted parameters indicate a growth delay, compared to cotton monoculture, of 11.8 d in the 3:1 system, 6.3 d in the 3:2 system, 6.9 d in the 4:2 system and 5.6 d in the 6:2 system. Estimated growth rate during the linear growth phase was lowest in the 6:2 system (5.9 g m −2 d −1), significantly greater in the 3:1 (7.0 g m −2 d −1), 4:2 (7.7 g m −2 d −1) and 3:2 (8.4 g m −2 d −1) systems, and greatest, but not significantly different from 3:2 and 4:2 systems, in the monoculture (8.9 g m −2 d −1). These results are interpreted in terms of the competitive effect of wheat during the seedling phase of cotton, which is strongest in the 3:1 system, causing a comparatively long growth delay, and the ability of the cotton leaf canopy to intercept radiation after wheat harvest, which is diminished in the 6:2 system due to the large distance between cotton rows, resulting in a comparatively low rate of linear growth. Effects of intercropping on the quality of cotton were minor and mostly below detection threshold.

The Effect of Johnsongrass (Sorghum halepense (L.) Pers.) Densities on Cotton Yield

Cotton is an important crop in Turkey. Johnsongrass is one of the worst weeds in cotton fields worldwide. Field experiments were carried out in 1992, 1997 and 2002 to show the effect of johnsongrass densities on cotton yield. Johnsongrass densities were 0, 1, 2, 4, 8, 16 and 32 plants per 8 m and 0, 3, 6, 8, 11, 14 and 22 plants per 4 m of cotton row. Data were fitted to equations Y = 1/(a+b*X8) in 1997 and 2002 for the number of johnsongrass in 8 m of row length and Y = 1/(a+b*X4(-1/2)) in 1992 and 1997 for the number of johnsongrass in 4 m of row length. Cotton yield was affected by all johnsongrass densities. One johnsongrass plant in 8 m of cotton row decreased cotton yield 4.82 and 9.42% in 1997 and 2002, respectively.

Cabin Field (review)

Reviewed by: Cabin Field Julia Zay (bio) Cabin Field (2005) DIRECTED BYLaura Kissel Laura Kissel's new film Cabin Field (2005) picks up where her previous work Finding Lula (2002) leaves off, as it attempts to read the surface of the land for evidence of what humans have done there. Through this film Kissel paints a portrait of a site, a mile-long parcel of agricultural land in rural south-central Georgia, and of landscape more generally, marked and remarked by human use through time. Her task in making this film is excavation, pursued through media old and new: oral histories, maps, digital video, home movies, satellite imagery, and archival film footage. Cabin Field weaves together these materials to manifest, rather than simply tell about, the complexity of a single piece of land called Cabin Field and, more generally, of the unrecognized richness of our landscape. Much contemporary experimental film and video that makes use of archival footage does so less as a means to directly illustrate an idea or provide a window onto some past reality than as a method for reflecting on the very idea of "history" or "representation" or "cinema," true to modernist strategies of reflexivity. Documentary filmmaking conventions dictate that archival footage be used primarily in the service of a film's claims to truth, whether to provide visible evidence of a specific event, person, et cetera, or to paint a general impression of an era or place. In Cabin Field, an experimental documentary or essay film, these differing uses for archival material collide in important ways. "Important" because as much as Kissel's film contributes to a body of knowledge about agricultural life and cultural landscapes in south Georgia, it also significantly challenges quaint renderings of farm life and fields as aesthetic objects as well as conventional methods for telling the story of a place. While the film is, in the tradition of documentary, about a specific piece of land, the people who have lived and worked on it for the past fifty-odd years, and the dynamics of race and gender in the rural South more generally, it is also, in an experimental tradition, as much about the languages and media we use to document and narrate our understanding of place and culture. Cabin Field weaves a visually dense fabric of archival and original footage and images, combining transferred 16mm film from the Fox Movietone News and Fox News collections at the University of South Carolina Newsfilm Library and the Andrew Avery Home Movie Collection at the University of Georgia Libraries' Walter J. Brown Media Archives, original 16mm film, digital video, and photographs. The film opens on a vividly colored satellite image of a large area of what appears to be agricultural land but looks more like abstract, irregular shapes marked with lines in shades of green and brown. The image starts to spin as we zoom in on it, as if tumbling and falling to the ground far below. More muted, much closer photographs of the area [End Page 124] taken from the U.S. Geological Survey emerge as the satellite image fades out. The almost treeless surface of the land resembles faintly stained paper; decades-old patterns made by the planting of cotton rows, invisible at ground level, here form their own kind of watermark on the land. These are the kinds of archival images everyday geographers are becoming more familiar with as applications like Google Earth and Web sites like Terra-Server now allow Internet users to view high-resolution images of the surface of the Earth and zoom in on precise addresses at the click of a button. All of this has the effect of defamiliarizing these archival images and the land itself, prompting us to consider the natural landscape as something that is made, something covered in marks, signs, and patterns to be deciphered, something discursive, written and written upon. Geographers and landscape historians use the concept of "landscape autobiography" to describe how a person's life and the "life" of a physical place can be understood as mutually constitutive. To write any history of a place, environment, or landscape one must actually develop an intimate familiarity...

Spurred anoda (Anoda cristata) interference in wide row and ultra narrow row cotton

A field experiment was conducted in 2000, 2001, and 2002 at Stoneville, MS, to determine the effect of spurred anoda interference on yield loss of two cotton cultivars, ‘Delta Pine 5415’ and ‘Pima S-6’, grown under wide (1 m) (WR) and ultra narrow (0.25 m) row (UNR) spacings. The relationship between spurred anoda density and dry weight per plot was linear each year. At a spurred anoda density of 8 m−2, spurred anoda dry weight per plot was 507, 322, and 777 g m−2in 2000, 2001, and 2002, respectively. However, spurred anoda did not interfere with seed cotton yield in 2001, which was probably attributable to the low branch development in that year. Yield losses exceeded 55% at a spurred anoda density of 8 m−2compared with controls in both WR and UNR. The effect of spurred anoda density on boll numbers was nearly identical in 2000 and 2002, regardless of cotton cultivar and row spacing. Boll weights decreased in response to spurred anoda interference. Spurred anoda interference resulted in a decrease in cotton branch dry weight in WR but not in UNR. The yield decrease as a result of spurred anoda interference in WR was due to reduction in boll retention or fruiting sites (predicated on a decrease in branch weight). However, in UNR, the yield decrease was due to plant mortality; the plant density of both cotton cultivars decreased by one plant for each additional spurred anoda, but the yield per plant for surviving plants remained constant. Neither WR nor UNR cotton had significant advantage in response to spurred anoda interference. The decreased boll weight observed in UNR, and the failure to increase boll numbers m−2to compensate for decreased boll weight in UNR compared with WR, may limit its appeal to cotton producers.

Management of the pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) by mating disruption in cotton fields

The efficacy of mating disruption of pink bollworm Pectinophora gossypiella (Saunders) was evaluated by monitoring its population with pheromone baited traps as well as by sampling flowers and bolls to record damage levels in cotton fields in 1988 and 1989, in central Greece. PB-rope dispensers were used at a rate of 1000 per hectare in the treated fields, each field covered an area of 10 and 15ha in the first and second year, respectively. These treated fields were compared with control fields in which 2–3 insecticide sprays were applied. The dispensers reduced pink bollworm catches in pheromone traps and reduced crop damage. The direction of cotton rows in relation to the prevailing wind had a significant effect on moth catches and needs to be taken into account when using dispensers. Mating disruption was effective in preventing damage when applied early season, but damage levels were not proportionally reduced in relation to the reduction of trap catches. Sufficient gossyplure for reducing moth catches in the traps was in pheromone dispensers even 90 days in the field.

Feeding the Jewish Soul in the Delta Diaspora

Click for larger view Mention "The Delta" and vivid images come to mind of a dramatic, flat landscape etched by rows of cotton and bounded by the Mississippi River. Less visible, but nonetheless present, are the adapted folklore and foodways of a transplanted culture, for feeding the Jewish soul, both spiritually and physically, has challenged Delta Jews from their first arrival in the region through today. Photograph courtesy of the author.

Effects of tillage, ridging and row spacing on seedling emergence and yield of cotton

Field experiments were conducted at Harran Plain on a clay silt soil (Xerosol in FAO/UNESCO soil classification) in Southeast of Turkey in 1996 and 1997 to study the effects of cotton planting system, tillage method, and row spacing on the performances of cotton ( Gossypium hirsutum L.), such as seedling emergence and yield. The tillage methods evaluated were: traditional (inversion) with a mouldboard plough (M) and conservation (non-inversion) with chisel tine (C). The seedbeds studied were: normal planting system (NS) with no-ridging, and ridge planting system (RS). Results showed that mouldboard plough had slightly greater yield than chisel in each year but the difference was not significance in 1997. Non-ridging had the second best emergence rate and yield according to 2 years mean. Ridging with chisel in 70 cm row spacing produced the highest seedling emergence for both years, but the difference was not significance in 1997. The yields obtained for ridging with mouldboard plough from 70 cm row spacing in 1996, and for ridging with mouldboard plough from 76 cm in 1997 were superior to the other applications. Finally 70 cm row spacing produced the highest seedling emergence and yield in both years regardless of the treatment. Row spacing of 90 cm resulted in the lowest seedling emergence and yield in both years regardless of the treatment. The results indicate that ridging can be used instead of non-ridging with 76 cm row spacing (suitable for mechanical harvesting) which gave similar yield to the ridging with 70 cm row spacing in 1997, and both of the planting systems with 76 cm seem to be suitable to mechanical harvesting.

Thermal infrared radiative transfer within three‐dimensional vegetation covers

The angular distribution of thermal infrared (TIR) radiation emitted by vegetation covers can vary widely depending on environmental conditions and canopy structure. As an aid in the interpretation of TIR remotely sensed data from vegetated surface with incomplete canopies, we developed a three‐dimensional radiative transfer model in the thermal infrared domain. The model simulates the TIR radiative budget and upward spectral radiance of vegetation covers. The model is an extension to the TIR region of the DART (Discrete Anisotropic Radiative Transfer) model developed for the short wave domain. Radiative transfer simulation relies on discrete 3‐D scene representations, which include any distribution of trees and ground covers, possibly with topography. Propagation of emitted and scattered radiation is tracked with a ray‐tracing approach and the discrete ordinate method. The model was successfully tested against a physically based model for homogeneous canopies, and a partial validation was carried out with directional TIR measurements on a cotton row crop. Model simulations are presented to illustrate the influence of the canopy geometric structure on the directional apparent temperature of hypothetical vegetation covers.

Effects of Surface Application of MSW Compost On Cotton Production – Soil Properties, Plant Responses, And Nematode Management

Equipment was modified and/or developed for broadcast and banded applications of municipal solid waste (MSW) compost at selected rates to agricultural land for cotton production. Replicated tests were conducted for four years to determine the effects of compost on soil properties, crop yield, and nematode populations. Soil type in the test field was Faceville loamy sand. Broadcast application of compost significantly reduced soil compaction in the top 30 cm of soil in cotton rows and row-middles compared to no compost application. Banded application did not affect compaction in the row middles. Columbia lance nematode densities decreased in all compost-treated plots during all four years of study. Several plots treated with compost had nematode densities comparable to those found in the plots treated with Temik 15G nematicide. Compost application significantly increased the soil organic matter content and soil nitrogen content at six and 14 weeks after planting. However, the compost did not affect the leaf nitrogen content of the cotton plant during the same sampling periods. In 1996, 1997, and 1998, all rates of added compost significantly increased seed cotton yield. Yield increase was proportional to application rate. There were very few carry-over compost effects from each previous year's treatments on either soil organic matter, soil nitrogen, or seed cotton yield.