Tomato (Lycopersicon esculentum Mill.) was grown with drip irrigation on a fine sand and on a fine sandy loam to evaluate the effect of N and K time of application on yield. On the sandy soil, 196–112 kg of N–K/ha was applied with 0%, 40%, or 100% preplant with 100% or 60% applied in six or 12 equal or in 12-week variable applications. Marketable fruit yields were lowest with 100% preplant, intermediate with 100% drip-applied, and highest with 40% preplant with 60% drip-applied. With 100% drip-applied, yields were highest with 12 even than with six even weekly applications or with 12 variable N and K applications. With the 40% preplant, timing of application had little effect on yield. On the sandy loam soil in 1993, where only N was applied (196 kg·ha–1), yields were highest with 100% preplant, intermediate with 40% preplant and 60% drip-applied, and lowest with all N drip-applied. In 1994, when excessive rains occurred, yields were similar with all preplant and with split-N applications.
S.J. Locascio, F.M. Rhoades, S.M. Olson, G.J. Hochmuth and E.A. Hanlon
Georges T. Dodds, Leif Trenholm, Ali Rajabipour, Chandra A. Madramootoo and Eric R. Norris
In a 2-year study (1993-94), tomato (Lycopersicon esculentum Mill. `New Yorker') plants grown in a sandy loam soil in field lysimeters were subjected to four water table depth (WTD) treatments (0.3, 0.6, 0.8, and 1.0 m from the soil surface). In 1994, precipitation during the flowering stage was far above average and apparently led to waterlogging in the shallowest WTD treatment, while in the drier year (1993), the deepest WTD treatment suffered from drought stress. In general, over the 2 years, the 0.6-m WTD showed the best yields and largest fruit, while the 1.0-m WTD showed the lowest yields and smallest fruit. However, the incidence of catfacing, cracking, and sunscald was generally higher in the 0.6 m WTD treatment and lower in the 1.0-m WTD treatment. Furthermore, fruit firmness was generally greatest for the two deeper WTD than for the shallower WTD. To strike a balance between yield and quality, a WTD of between 0.6- and 0.8-m is recommended for tomato production on sandy loam soils.
Donita L. Bryan, W. Todd Watson, Leonardo Lombardini, John J. Sloan, Andrew D. Cartmill, Geoffrey C. Denny and Michael A. Arnold
Tree transplanting practices influence plant survival, establishment, and subsequent landscape value. However, transplanting practices vary substantially within the horticultural industry. Of particular importance is the location of the root collar relative to soil grade at transplant. The objective of this study was to determine the effects of factorial combinations of planting depths, root collar at grade or 7.6 cm either above or below grade, and soil amendments on container-grown (11 L) Quercus virginiana Mill. Soil treatments included a tilled native soil (heavy clay loam, Zack Series, Zack-urban land complex, fine, montmorillonitic, thermic, udic paleustalfs), native soils amended with 7.6 cm of coarse blasting sand or peat that were then tilled to a depth of 23 cm, or raised beds containing 20 cm of sandy loam soil (Silawa fine sandy loam, siliceous, thermic, ultic haplustalfs). A significant (P ≤ 0.05) block by soil amendment interaction occurred for photosynthetic activity. Incorporation of peat significantly decreased the bulk density of the native soil. Planting depth had no significant effect on photosynthetic activity or stem xylem water potential at 3 months after transplant. Soil water potentials did not statistically differ among treatments.
Nektarios Panayiotis, Tsiotsiopoulou Panayiota and Chronopoulos Ioannis
Four substrates were investigated for their efficacy as roof garden vegetative layers. The substrates comprised a sandy loam soil (S), sandy loam soil amended with urea formaldehyde resin foam (S:F) in a proportion of 60-40 v/v, sandy loam soil amended with peat and perlite (S:P:Per) in a proportion of 50-30-20 v/v and peat amended with urea formaldehyde resin foam (P:F) in a proportion of 60-40 v/v. The substrates were evaluated for their physical and chemical properties and their capacity to sustain growth of Lantana camara L. Physical and chemical evaluation included weight determination at saturation and at field capacity, bulk density determination, water retention, air filled porosity at 40 cm, pH and EC. When compared to the control (S) a weight reduction of 16.8%, 23.9% and 70.3% was obtained at field capacity with S:F, S:P:Per and P:F substrates respectively. Bulk density was reduced by 46%, 43% and 95%, in substrates S:F, S:P:Per and P:F, respectively, compared to the control substrate S. Air-filled porosity at 40 cm was slightly increased for substrate S:F while it was substantially increased for substrate P:F. The pH response between the initiation and the termination of the study was similar for the four substrates. EC decreased in substrates S and S:P:Per but increased in substrates S:F and P:F. Plant growth was monitored as shoot length, shoot number, main shoot diameter and the number of buds and flowers. Substrates S and S:F resulted in similar plant growth, while substrate S:F promoted flowering. Substrate S:P:Per induced slow plant growth during the first 6 months which subsequently increased resulting in a final growth that was satisfactory and comparable to the S and S:F substrates. Substrate P:F did not support sufficient plant growth and its use should be considered only in special cases where reduced weight of the roof garden is imperative.
Kathy Kelley and Dave Ramos
Fifty trees each of 1-year-old Paradox rootstock June-budded to `Chandler' walnut and 2-year-old Paradox whipgrafted to `Chandler' were planted in a 28 × 28-ft spacing on a Hanford sandy loam soil. Ten trees of each type were selected at time of planting and the number of roots, individual root diameter, trunk diameter, root dry weight, scion dry weight, and total dry weight were compared. All parameters, with the exception of root number, were significantly greater for the grafted 2-year-old rootstocks. Growth of the trees measured as trunk circumference 20 cm above the graft union was significantly greater for the grafted 2-year-old rootstocks following the first season. There was no significant different in trunk circumference between the 1- and 2-year-old rootstocks following the second or third growing seasons.
S.B. Sterrett, B.B. Ross and C.P. Savage Jr.
New Jersey `Syn 4' asparagus (Asparagus officinalis, L.) was grown on a sandy loam soil to compare plant survival and yield of asparagus grown from crowns and transplants under four irrigation treatments: sprinkler (SPR), surface trickle (ST), subsurface trickle (SST), and no irrigation (NI). While plant survival of crowns was not appreciably influenced by any irrigation treatment, survival of transplants was significantly increased by SST. Total and marketable yields from crowns and transplants were similar in the first harvest season (year 3). However, in years 4 and 5, the yield of crowns was higher than that of transplants. Subsurface trickle increased yield from transplants in years 4 and 5 and increased yield from crowns in year 5. All irrigation methods significantly increased both spear production (spear/ha) and average spear weight. Subsurface trickle irrigation resulted in the largest increase over NI in total yield and spear production.
Craig A. Storlie, Philip E. Neary and James W. Paterson
The effects of fertilizer rates and application frequency on drip-irrigated bell peppers (Capsicum annuum L.) were evaluated at two sites in 1992 and one site in 1993 in southern New Jersey. Yield and fruit quality were greatest with 158N-69P-131K lb/acre at the site with a sandy loam soil. Yield and fruit quality responded to additional fertilizer at sites with loamy sand soils. Average marketable fruit weight increased with increasing fertilization rate at one of the two loamy sand sites. The incidence of sun scald decreased with increasing fertilization rate. Increasing the frequency of drip-applied fertilizer from 11 to 22 days did not affect yield or fruit quality in either year when the same amount of fertilizer was applied. These results show that maximizing the yield of bell peppers grown on loamy sand soils in New Jersey may require higher fertilization rates than previously recommended.
George H. Clough
Potato (Solanum tuberosum) cv. `Russet Burbank' response to source of side-dress Ca fertilization applied at 0, 28 and 56 kg·ha-1 Ca on fine sandy loam soil was evaluated. Side-dress Ca source and rate did not affect number or total weight of tubers/hill, average tuber weight, or tuber macronutrient concentrations at mid-season. Tuber B concentration was significantly greater with the 12-0-0-10.5 source as compared to the check. Tuber Fe concentration decreased linearly as 22-0-0-7 rate increased from 0 to 56 kg·ha-1 Ca. No other micronutrient concentration was affected by the applied treatments. Calcium fertilization had no effect on tuber yield, grade distribution, or specific gravity. The predominant internal defect observed was brown center, which was reduced at harvest by side-dress Ca application. Internal quality and french fry color were evaluated after storage for 4 months.
Blaine R. Hanson, Donald M. May and Larry J. Schwankl
The effect on crop yield of drip-irrigation frequencies of two irrigations per day (2/d), one irrigation per day (1/d), two irrigations per week (2/week), and one irrigation per week (1/week) was investigated for lettuce (Lactuca sativa), pepper (Capsicum annuum), and onion (Allium cepa) grown on sandy loam and processing tomato (Lycopersicon esculentum) grown on silt loam during experiments conducted during 1994 to 1997. All treatments of a particular crop received the same amount of irrigation water per week. Results showed that the 1/week frequency should be avoided for the shallow rooted crops in sandy soil. Irrigation frequency had little effect on yield of tomato, a relatively deep-rooted crop. These results suggest that drip irrigation frequencies of 1/d or 2/week are appropriate in medium to fine texture soils for the soil and climate of the project site. There was no yield benefit of multiple irrigations per day.
Donald R. Hodel, Peter J. Beaudoin, A. James Downer and Dennis R. Pittenger
In a study in southern California, five species of palms [king palm (Archontophoenix cunninghamiana), mediterranean fan palm (Chamaerops humilis), queen palm (Syagrus romanzoffiana), windmill palm (Trachycarpus fortunei), california fan palm (Washingtonia filifera)] grown in 1-gal containers were planted in 12 × 12 × 12-inch holes in sandy loam (five species) and in clay loam (two species) with the backfill amended using a commercially available, composted, nitrogen-stabilized douglas fir (Pseudotsuga menziesii) shavings product incorporated at 0%, 25%, and 50% by volume. After 18 months, all palms were fully established. Crown volume, stem diameter, visual quality, quantity of new leaves produced, and percent total nitrogen, potassium, and magnesium in leaves did not differ significantly among the three treatments for all species or among treatments within a species. Thus, in this study there was no benefit from amending the backfill with this type of organic amendment when planting palms.