Sod-based production systems have been successful in the southeastern and mid-Atlantic regions of the United States as an alternative to conventional tillage systems. However, research comparing these systems in North Carolina is limited. Th erefore, research was conducted at four locations in North Carolina to compare corn (Zea mays L.), cotton (Gossypium hirsutum L.), peanut (Arachis hypogaea L.), and soybean [Glycine max (L.) Merr.] yield when these crops were strip tilled following 4 yr of continuous tall fescue (Shedonorus phoenix Scop.) vs. 4 yr of either corn or cotton grown in no tillage or strip tillage. Cotton yield was higher following tall fescue compared with yield following agronomic crops. In contrast, yield of corn was lower following tall fescue compared with agronomic crops while peanut and soybean yields were not aff ected by previous cropping history. Additional treatments in peanut included conventional tillage following both cropping systems, and pod yield was lower when peanut was strip tilled into either tall fescue or residue from corn or cotton compared with conventional tillage systems. No major diff erences in soil bulk density at depths of 0 to 8 cm or 8 to 16 cm were noted when comparing tall fescue or agronomic crops either in strip tillage or nontilled zones. Populations of soil parasitic nematodes were oft en lower in peanut following tall fescue than when following agronomic crops. Th ese experiments indicate that sod-based systems may be an eff ective alternative to reduced tillage systems, especially for cotton. However, yield benefi ts were not observed for peanut or soybean and corn was negatively aff ected by tall fescue.Abbreviations: CBR, Cylindrocladium black rot; %ELK, percentage of extra large kernels; %FP, percentage of fancy pods; %OK, percentage of other kernels; %SMK, percentage of sound mature kernels; %SS, percentage of sound splits; %TSMK, percentage of total sound mature kernels; TSW, tomato spotted wilt.

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Summary During a nematode biodiversity survey from 2012 to 2014 in Shenzhen, China, ten nematode populations (SZX1301–SZX1310) of Xiphinema were recovered from rhizosphere of different plants, namely Acacia mangium (SZX1306), A. confuse (SZX1309), Blechnum orientale (SZX1301, SZX1302, SZX1307, SZX1308), Litchi chinensis (SZX1304, SZX1310) in Tianxinshan and Gleichenia linearis (SZX1303, SZX1305) in Yangmeikeng environmental monitoring sites. Morphological and molecular profiles of these populations were determined. Three species of Xiphinema, i.e., X. hunaniense Wang & Wu, 1992, X. brasiliense Lordello, 1951 and X. americanum Cobb, 1913 sensu lato were identified using morphological characters and molecular data of partial 18S and 28S D2–D3 rDNA expansion segments. Four populations (SZX1301–SZX1304) were X. hunaniense, one population (SZX1305) X. brasiliense, and five populations (SZX1306–SZX1310) X. americanum s.l.. Phylogenetic analysis based on sequences of the 28S rDNA D2–D3 expansion segment revealed these three species are all distinct species and supported a close relationship with their corresponding species. This is the first report of X. hunaniense, X. brasiliense and X. americanum s.l. in their hosts except for L. chinensis.

A new species of Paurodontoides, P. siddiqii n. sp., is described and illustrated based on its morphological, morphometric, and molecular characters. The new species is characterized by a female 550–729 μm long, lip region continuous with body contour, stylet length 7.0–8.0 μm long or c. 1.0–1.2 times the lip region diameter, lateral fields with four smooth incisures, excretory pore at 85–125 μm from anterior end located at the base of the pharyngeal bulb or posterior to it, basal pharyngeal bulb with a short posterior extension projecting into the intestine, monodelphic–prodelphic reproductive system with prominent 19–22 μm long post-uterine sac, and elongate conoid tail with a filiform terminus. The new species is compared with two known species of the genus. It differs from the type species of the genus, P. linfordi, by having slightly shorter stylet, lateral field with smooth incisures, different position of the excretory pore, and absence of male. Compared to P. latus, the new species has a shorter body, shorter stylet, different position of the excretory pore, female tail shape and absence of male. The new species was also compared with close species of the genus Paurodontus because of lateral field marked with four lines, asymmetrical stylet knobs and absence of male. Molecular phylogenetic studies of the new species using partial sequences of 18S rDNA revealed that it forms a clade with a species of the genus Ficotylus. In phylogenetic analyses using partial sequences of the 28S rDNA D2-D3 domain, the new species formed a monophyletic group with a species of the genus Veleshkinema and Sphaerularia spp. (Sphaerulariinae).

Research was conducted in North Carolina from 2001 to 2006 to determine disease development, parasitic nematode population in soil, crop yield, and cumulative economic return in rotation systems including corn, peanut, and tobacco. Specific rotations included two consecutive cycles of corn‐corn‐peanut, corn‐tobacco‐peanut, or tobacco‐corn‐peanut; five years of corn followed by peanut, and corn‐corn‐tobacco‐corn‐corn‐peanut. In the final year of the experiment when only peanut was planted, the Cylindrocladium black rot (caused by Cylindrocladium parasiticum) (CBR)‐susceptible cultivar Gregory and the CBR‐resistant cultivar Perry were included. Increasing the number of years between peanut plantings increased yield of peanut in the final year of the experiment when Gregory was planted but not when Perry was planted. Incidence of CBR was highest when peanut was planted twice during the duration of the experiment compared with only once. No difference in ring nematode was observed regardless of rotation in the final year of the experiment. The highest soil population of stunt nematode was noted when five years of corn was followed by peanut with the lowest soil population of this nematode noted following two cycles of tobacco‐corn‐peanut. Cropping systems that included tobacco provided higher cumulative economic returns regardless of rotation sequence in most instances.