Squash (Cucurbita pepo L. var. pepo) plants were grown on black polyethylene mulch or on bare ground, with trickle or furrow irrigation, and received only natural rainfall, or natural rainfall plus half or all of the estimated supplemental irrigation water required as determined by an irrigation scheduling program. The squash roots predominate in the upper 6 inches of soil throughout the season, with no less than 60% of the root mass located in this layer. The proliferation of roots increased as they extended horizontally from the vertical center line of the plant from 0 to 24 inches. Neither the irrigation treatments nor black polyethylene mulch had any influence on the pattern of root development. Water stress, however, reduced the size of the root system and the crop yield. Yields were not influenced by either furrow or trickle irrigation on the short rows that were used in this study. However, black polyethylene mulch and full irrigation offered the best chance of maximizing squash yields under the conditions of this study.
James E. Ells, Ann E. McSay, E. Gordon Kruse, and Gregory Larson
Daniel I. Leskovar and Ronald R. Heineman
Two studies were conducted to determine how greenhouse irrigation systems alter root elongation, root morphology, shoot growth, and water status of `TAM-Mild Jalapeño-1' pepper (Capsicum annuum L.) seedlings. Transplants were grown in containerized trays for 48 days in a greenhouse. Irrigation systems were 1) flotation (FI), 2) 28 days FI plus 14 days overhead (OI; FI + OI), 3) alternate OI and FI (OI–FI), and 4) OI. FI and OI–FI transplants maintained a uniform lateral root length increase between 20 and 41 days after seeding (DAS). In FI + OI and OI transplants, lateral root elongation tended to plateau at ≈31 DAS; however, by increasing the number and length (33%) of basal roots, OI transplants had a total root growth compensation during the remaining growth period. At 41 DAS, OI transplants had a higher shoot: root ratio (S: R = 5) and maintained a higher shoot water potential (Ψstem = –0.58) than FI transplants (S: R = 3; Ψstem= –0.69 MPa, respectively). In the second study, OI transplants maintained higher Ψstem than FI transplants. The latter had a lower stomatal conductance and photosynthesis rate than OI and FI + OI transplants. FI may be used to lower the S: R ratio and promote hardiness in jalapeño transplants.
Daniel I. Leskovar, Daniel J. Cantliffe, and Peter J. Stoffella
`Sunny' tomato (Lycopersicon esculentum Mill.) containerized transplants were grown with the standard or conventional systems (SS) and with recently developed flotation systems (FS). Standard system and FS transplants, and direct-seeding using coated seeds were evaluated in the field for root and shoot growth and yield at Parrish, Bradenton, and Naples during fall, winter, and spring plantings. Plant growth characteristics were measured weekly before, during, and after transplanting or sowing. In the Parrish and Bradenton Fall 1987 and Bradenton Spring 1988 experiments, SS transplants had greater leaf area, root volume, shoot dry weights, and shoot: root ratios than FS transplants. During early development, the FS transplants had more lateral root growth than SS transplants, but had similar total root growth and horizontal and vertical root distribution after transplanting in the field. Transplants and direct-seeded plants allocated 72% of the total root mass in the upper 0 to 10 cm of the soil. In Fall 1987, SS transplants had between 29% and 41% more fruit yield than FS transplants at Bradenton and Parrish, respectively. In the Naples Winter 1988 and Parrish and Bradenton Fall 1989 experiments, both transplant types had similar fruit yields, but more than direct-seeded plants. Transplants grown with the flotation system are recommended for use provided that seedlings are grown and maintained with minimum hardening before establishment in the field.
Kevin R. Kosola, Beth Ann A. Workmaster, James S. Busse, and Jeffrey H. Gilman
carry roots and organic matter up to a capture screen. High-velocity air excavation of roots is an alternative method for root sampling that allows relatively rapid isolation of roots from an individual tree; it is usually not feasible to identify the
Meiling Zhang, Ming Chen, Zhen Wang, Ting Wu, Yi Wang, Xinzhong Zhang, and Zhenhai Han
collected after +Fe condition (40 μM FeNaEDTA) or −Fe condition (0 μM FeNaEDTA) for 3 d for RNA extraction and freezing-drying microtomy. Freezing-drying microtomy and SR-μXRF. Root samples of 1-cm length were cut off from the root tip and embedded quickly
Peter B. Ojong, Victor Njiti, Zibao Guo, Ming Gao, Samuel Besong, and Sandra L. Barnes
(50), 12 (95). The percent dry weight (%DW) of flavonoids in the leaf and root samples were calculated using the following formula: %DW = (100 × μg·mL −1 concentration × 100 mL solvent × 10 −6 g·μg −1 )/1 g sample. The expression 10 −6 g·μg −1 is a
Carmen Feller and Matthias Fink
water, cut, and mixed. Then three subsamples were taken from the mixed root sample. The first subsample, ≈300 g fresh matter, was squeezed out, resulting in 10 mL root sap, which was stored in test tubes to avoid dehydration. Refraction of the sap was
Kevin R. Kosola and Beth Ann A. Workmaster
. Effect of bed age (years) on ericoid mycorrhizal (ERM) colonization (percent root length) of cranberry. Data from root samples collected from cultivated beds across eight different cranberry farms in Wisconsin in 2002 (farms 1–8, Table 1 ). ( A
Yusuke Ii, Yuichi Uno, Michio Kanechi, and Noboru Inagaki
were observed in all samples. Root samples from a normal asparagus cultivar were also tested, and males and females could be determined by their banding patterns ( Table 2 ). Although the validity of the method could only be determined when the
Scovia Adikini, Settumba B. Mukasa, Robert O.M. Mwanga, and Richard W. Gibson
/mottling. ( I ) Vein chlorosis. Table 1. Proportion of sweetpotato sprouts tested positive for virus infection from root samples selected after field harvest from Makerere University Agricultural Research Institute, Kabanyolo (MUARIK) and the National Semi Arid