Management practices can influence NO3‐N content and movement in the soil. We examined the influence of 3 yr of tillage [no‐till (NT), chisel (CH), and moldboard (MB)], cover crop [hairy vetch (Vicia villosa Roth) (HV), and no hairy vetch (NHV)], and N fertilization (0, 90, and 180 kg N ha−1) on residual NO3‐N content and movement on a Norfolk sandy loam (fine‐loamy, siliceous, thermic, Typic Kandiudults) under tomato (Lycopersicon esculentum Mill) in central Georgia. Because of low N recovery by tomato, NO3‐N content in the soil increased with depth, regardless of treatments, and ranged from 127 to 316 kg ha−1 at 0‐ to 120‐cm depth in the fall (September 1997). The content increased with increasing rate of N addition from cover crop residue and N fertilizer. From fall to spring (March 1998), 22 to 58% (37 to 129 kg NO3‐N ha−1) of this content was lost, mostly due to leaching. Greater loss occurred in NT than in CH or MB, with HV than with NHV, and with 180 or 90 than with 0 kg N ha−1. Similarly, greater loss at 0‐ to 60‐cm than at 60‐ to 120‐cm depth and significant correlation between soil NO3‐N and clay concentration with depth indicates that NO3‐N moved from the surface layer to the underlying clay layer, where it moved slowly. Nitrate‐N content and movement in the soil from cover crop residue and N fertilizer were similar. Minimum tillage reduced NO3‐N movement compared with NT, yet avoided the negative effects on soil and water quality associated with MB. Although HV increased tomato N uptake and recovery, it was not effective in reducing NO3‐N content and movement compared with N fertilizer.

The influence of tillage [no-till (NT) vs. moldboard plowing (MP)], cover crop [hairy vetch (Vicia villosa Roth) (HV) vs. no hairy vetch (NHV)], and N fertilization (0 and 180 kg·ha–1 N) on root distribution and growth rate of tomato (Lycopersicon esculentum Mill.) transplants was examined in the field from May to August in 1996 and 1997. Experiments were conducted on a Norfolk sandy loam (fine-loamy, siliceous, thermic, Typic Kandiudults) in central Georgia. Root growth was estimated every 1 to 2 weeks with minirhizotron tubes installed in the plot. Roots were well distributed at soil depths between 1 and 58.5 cm and a maximum root count of 3.14 roots/cm2 soil profile area was found at 19.5-cm depth with MP and no N fertilization in 1996. In general, NT with HV or with 0 kg·ha–1 N increased root proliferation at a depth of 6.5 to 19.5 cm, while MP with 180 kg·ha–1 N increased root proliferation at greater depths. Total root count between 1 and 58.5 cm was not influenced by management practices, but increased linearly at rates of 0.35 roots/cm2 per day from 20 June to 11 July 1996, and 0.03 roots/cm2 per day from 16 May to 5 Aug. 1997. Root growth thereafter was minimal. Because of the higher temperature during early development, growth rate and number of roots were greater in 1996 than in 1997. Superior moisture conservation, accompanied by increased N availability, may have increased root proliferation in the surface soil in NT with HV or with 0 kg·ha–1 N compared with NT with NHV or with 180 kg·ha–1 N, and MP with or without HV or with or without N fertilization. Root growth, however, was not related with aboveground tomato yield.

The objectives of this study were to know the effect of repeated freeze-thaw cycles of beef on the sensory, physicochemical quality and microbiological assessment. The effects of three successive freeze-thaw cycles on beef forelimb were investigated comparing with unfrozen fresh beef for 75 d by keeping at −20±1℃. The freeze-thaw cycles were subjected to three thawing methods and carried out to know the best one. As the number of freeze-thaw cycles increased color and odor declined significantly before cook within the cycles and tenderness, overall acceptability also declined among the cycles after cook by thawing methods. The thawing loss increased and dripping loss decreased significantly (p<0.05). Water holding capacity (WHC) increased (p<0.05) until two cycles and then decreased. Cooking loss increased in cycle 1 and 3, but decreased in cycle 2. pH decreased significantly (p<0.05) among the cycles. Moreover, drip loss, cooking loss and WHC were affected (p<0.05) by thawing methods within the cycles. 2-Thiobarbituric acid (TBARS) value increased (p<0.05) gradually within the cycles and among the cycles by thawing methods. Total viable bacteria, total coliform and total yeast-mould count decreased significantly (p<0.05) within and among the cycles in comparison to the initial count in repeated freeze-thaw cycles. As a result, repeated freeze-thaw cycles affected the sensory, physicochemical and microbiological qua- lity of beef, causing the deterioration of beef quality, but improved the microbiological quality. Although repeated freeze-thaw cycles did not affect much on beef quality and safety but it may be concluded that repeated freeze and thaw should be minimized in terms of beef color for commercial value and WHC and tenderness/juiciness for eating quality.

An experiment was carried out to study the effect of cattle slurry on maize fodder (Zea mays) production. Maize fodder was produced at 4 cattle slurry levels T 0 (0 ton/ha), T 1 (10 ton/ha), T 2 (12 ton/ha) and T 3 (14 ton/ha) in a randomized block design. Agronomic characteristics, plant heights, circumference of stems, number of leaves, leaf area and dry matter yield of maize fodder were measured. Maize plant height and stem circumference were significantly (p<0.01) influenced by the increasing rate of cattle slurry at 15, 30, 45 and 56 days after sowing. Number of leaves of fodder plants was not significant but leaf area was significant (p<0.05) among the treatment groups. The highest biomass yield (p<0.01) of maize fodder was observed in T 2 (44.0 ton/ha). For crude protein content, a significant difference (p<0.01) was observed in the treatment groups and the highest value was observed in T 2 (11.99%). Organic matter content of maize fodder showed a significant difference but ash, ADF and NDF contents showed no significant differences among treatment groups. From this study it may be concluded that the application of 12 tons of cattle slurry/ha was optimal for production of biomass and nutrient content of maize fodder.

Management practices can influence tomato (Lycopersicon esculentum Mill.) yield and N uptake. The effects of tillage (no-till, chisel plowing, and moldboard plowing), cover crop [hairy vetch (Vicia villosa Roth) vs. none], and N fertilization (0, 90, and 180 kg·ha-1 N) on transplanted tomato yield and N uptake were studied in the field from May to August in 1996 and 1997 on a Norfolk sandy loam (fine-loamy, siliceous, thermic, Typic Kandiudults) in central Georgia. Plowing increased fresh and dry fruit yield and N uptake in 1996 and N fertilization increased yield and N uptake in 1996 and 1997. Plowing also increased stem and leaf dry weights and N uptake from 40 to 118 days after transplanting (DAT) in 1996. Fertilization increased stem weight and N uptake with or without hairy vetch from 54 to 68 DAT in 1996 and stem and leaf weights and N uptake at 68 DAT in 1997. Both hairy vetch and N fertilization increased leaf N concentration in 1997. Recovery of N by the plants was lower with hairy vetch than with N fertilization, but was similar to or greater with 90 than with 180 kg·ha-1 N. We conclude that reduced tillage, such as chisel plowing, with 90 kg·ha-1 N can sustain tomato yield and N uptake, with reduced potentials of sediments and/or NO3 contamination in surface and groundwater.