A long-term experiment in the same site was planted to evaluate potential yield, nematode, and disease problems with tomatoes (Lycopersicon esculentum Mill.) in a strip-till system. Treatments consisted of conventional tillage (CT) and strip tillage (ST), rye (Secale cereale L.), wheat (Triticum aestivum L.), and perennial ryegrass (Lolium perenne L.) cover crops and a 2-year rye–tomato rotation. Results of the first 5 years indicate a decrease in tomato yield over time for both tillage treatments and cover crops. Tomato yields were lower following wheat and perennial ryegrass than rye. Strip-tillage reduced yield compared to conventional tillage in only 1 year out of 6. Yield increased overall for treatments in 1992, with highest yield in the rye–tomato rotation. Bacterial speck/spot symptoms on foliage, although minor, were significantly greater in ST than in CT plots during the last 3 years. No major consistent trends in incidence and severity of bacterial and fungal diseases and of disorders of fruit were evident during the 5-year period, and neither fruit yield nor quality were significantly affected by these factors. Root-knot nematodes (Meloidogyne hapla Chitwood) were numerically less numerous in the rye–tomato rotation than in other treatments; both root-knot and root lesion nematodes [Pratylenchus penetrans (Cobb)] tended to be less numerous under CT than under ST. Tomatoes grown under reduced tillage appear more sensitive to plant parasitic nematodes and preceding cover crops than in conventional tillage.
Alan W. McKeown, John W. Potter, R.F. Cerkauskas, and L. Van Driel
John P. Edstrom*, William Krueger, and Wilbur Reil
Orchard hedgerow production systems have been used successfully in fruit and nut crops in California for decades to enhance yield, particularly in the early years of production. English walnuts (Juglans regia) are compatible with hedgerow techniques under prime soil conditions but are thought to require deep well drained soil to be commercially productive. Combining the production techniques of micro-irrigation, close spacing, minimal pruning and frequent fertilization in almonds has improved yield substantially on soils exhibiting a shallow, course textured topsoil underlain with a dense clay layer. Paradox hybrid rootstock (J. regia × J. hindsii) has shown greater tolerance to root lesion nematodes and heavier textured or poorly drained soils than Northern California Black (J. hindsii). Fourteen years of evaluation (1986-99) using `Chandler' and `Howard' Ctvs English walnuts in a replicated field trial on marginal soil has shown that 1) yields of 6700 kg·ha-1 (inshell) are attainable under these substandard soil conditions 2) Paradox hybrid rootstock out-yields Northern California Black by 30% on both cultivars tested, 3) kernels of high commercial quality for can be produced for both cultivars and 4) slip plow soil modifications may not improve tree growth, yield or crop quality in drip irrigated walnut hedgerow plantings.
Michelle M. Leinfelder, Ian A. Merwin, Gennaro Fazio, and Terence Robinson*
We are testing control tactics for apple replant disease (ARD) complex, a worldwide problem for fruit growers that is attributed to various biotic and abiotic soil factors. In Nov. 2001, “Empire” apple trees on five rootstocks (M.26, M.7, G.16, CG.6210, and G.30) were planted into four preplant soil treatments—commercial compost at 492 kg/ha soil-incorporated and 492 kg·ha-1 surface-applied), soil fumigation with Telone C-17 (400 L·ha-1 of 1,3-dichloropropene + chloropicrin injected at 30 cm depth five weeks prior to replanting), compost plus fumigant combination, and untreated controls—at an old orchard site in Ithaca, N.Y. Trees were replanted in rows perpendicular to, and either in or out of, previous orchard rows. Irrigation was applied as needed, and N-P-K fertilizer was applied in 2001 to all non-compost treatments to compensate for nutrients in the compost treatment. After two growing seasons, the rootstock factor has contributed most to tree-growth differences. CG.6210 rootstock supported greater growth in trunk diameter, central leader height, and lateral shoot growth (P < 0.05), regardless of preplant soil treatments and replant position. Trees on M.26 grew least over a two year period. Replant growth was greater in old grass lanes than in old tree rows, despite higher root-lesion nematode populations in previous grass lanes. Growth responses to preplant soil fumigation were negligible. Preplant compost did not increase tree growth during year one, but did increase lateral branch growth in year two. Results thus far suggest that replanting apple trees out of the old tree-row locations, and using ARD tolerant rootstocks such as CG.6210, may be more effective than soil fumigation for control of ARD in some old orchard sites.
Dennis N. Portz and Gail R. Nonnecke
-(phosphonomethyl)glycine] applied with a hand wick applicator and then pre-emergent herbicide was applied (DCPA, dimethyl tetrachloroterephthalate) ( Bordelon et al., 2006 ). Strawberry plants for sampling of root-lesion nematodes were collected 25 Oct. 2005, 30 Oct. 2006, and 17
weed pressure is crucial for maximizing yields. Wheat Cover Crops Are Hosts for Root Lesion Nematode Root lesion nematode (RLN) is a ubiquitous parasite of red raspberry. Winter wheat is a common rotational crop between red raspberry removal and
Antonio J. Felipe
resistance ( Esmenjaud et al., 1997 ; Marull et al., 1994 ). In addition, ‘Felinem’ shows a moderate resistance to the root-lesion nematode Pratylenchus vulnus ( Pinochet et al., 2000 ). Resistance mechanisms to nematode are determined by hypersensitive
probably a standard diploid genotype as both the P. cerasifera and P. dulcis parents. Several original and similar clones were found in a nursery in Zaragoza, Spain. They were observed and tested for root-knot and root-lesion nematodes, salinity
Chrislyn Ann Particka and James F. Hancock
; Szczygiel and Profic-Alwasiak, 1989 ). Various Pythium species have also been identified as causal organisms ( Nemec and Sanders, 1970 ), and Pythium ultimum Trow is considered to be the most common one ( Wilhelm, 1998 ). The root lesion nematode
Andrew L. Thomas, Jackie L. Harris, Elijah A. Bergmeier, and R. Keith Striegler
known to vector Tomato ringspot virus in grapes, and root-knot and root lesion nematodes are known to cause economic damage to grapevines ( McKenry and Bettiga, 2013 ), efforts to explore the application of nematode-resistant rootstocks in midwestern U
Brad Geary, Corey Ransom, Brad Brown, Dennis Atkinson, and Saad Hafez
conducted in microplots and in the field confirmed that rapeseed ‘Humus’ and oil seed radish reduced the population of root knot nematodes and root lesion nematodes ( Pratylenchus penetrans ) and increased potato ( Solanum tuberosum ) quality and tuber yield