Prickly sida

Root elongation bloassay of root exudates. Only prickly sida root exudate significantly affected radish or tomato root elongation (Table II). It significantly inhibited radish root elongation and significantly stimulated tomato root elongation. 

Table XI. Effect of Ferulic Acid on Morningglory, Ragweed, Crabgrass, and Prickly Sida Seed Germination...

Morningglory Ragweed Crabgrass Without Prickly sida Carpel With Carpel... 

With the extraction procedure we employed (22), ferulic acid was isolated as the most inhibitory component in wheat straw. There could also be other unknown compounds in the straw which would not be evident with this procedure. In addition, we ignored the possible influence of toxin-producing microorganisms. Microorganisms may have influenced the phytotoxicity exhibited by the aqueous wheat extract in Table IX. Although the present study was not concerned with the phytotoxic effects of microbially decomposed wheat straw, an influence of microbial activity on ferulic acid phytotoxicity was observed. From the results shown in Table XI, it appears that the presence of the prickly sida seed carpel enhanced the inhibitory effects of ferulic acid. In addition to ferulic acid in test solutions containing prickly sida seeds with carpels, a second compound, 4-hydroxy-3-methoxy styrene, was also found to be present. This compound is formed by the decarboxylation of ferulic acid and was produced by a bacterium present on the carpel of prickly sida seed. The decarboxylation of ferulic acid was detected in aqueous solutions of ferulic acid inoculated with the bacterium isolated from the carpels of prickly sida seed. No conversion occurred when the bacterium was not present. 

It seems most likely that the presence of the styrene compound was at least partially responsible for the inhibition of prickly sida germination and root length, since ferulic acid alone (prickly sida seed without carpels plus ferulic acid) had no effect on prickly sida germination or root length (Table XI). The decarboxylation of phenolic acids to corresponding styrenes is known from studies on fungi and bacteria (60, 61). However, in a number of studies directly concerned with the microbial decomposition of ferulic acid, as well as other phenolic acids, no mention is made of any styrene compounds produced as a result of phenolic acid decarboxylation (62, 63, 64, 65). 

Medium-grain fatty rice bran was the best material for reducing weed emergence (Palmer amaranth Amaranthuspalmeri S. Wats, and ivyleaf momingglory Ipomoea hederacea Jacq. followed by sicklepod Senna obtusifolia (L.) H. S. Irvin Bameby, hemp sesbania Sesbania exaltata (Raf.) Cory and prickly sida Sida... 

Prickly sida Sida soinosa (L ) Fusarium lateritium (Nees) emend Snyder and Hans. Tween 80 (0.02%) 1 X 10 18 5... 

Figure 3. Effect of carbon source on efficacy and spore yield of Fusarium lateritum. Spore yield (A-A) was inversely related to virulence. Proprietary fermentation medium contained starch, glucose-starch, or glucose as the primary carbon source. Spores were harvested from the fermentor and immediately used at 10 spores/ml to inoculate prickly sida Sida spinosa L.) in the primary leaf growth stage. Plants were subjected to a 20-h dew period at 25° C, removed to greenhouses for observation, and evaluated 14 days after inoculation.

One of the advantages of methazole is its ability to kill efficiently in vines and orchards certain weeds that are difficult to control, such as Sida spinosa (prickly sida) and Convolvulus spp. (Butts and Foy, I974a,b Furness and Halawi, 1974). 

The phenyl tetrahydrophthalimides are primarily post-emergence herbicides for the control of broadleaf weeds, though they will show pre-emergence activity at higher rates of application. Flumiclorac-pentyl is a post-emergence herbicide for the control of broadleaf weeds such as cocldebur, common lambsquarters, jimsonweed, amaranthus, prickly sida, and velvetleaf in soybean and corn at 25-... 

Another area related to fluazolate (17) and pyraflufen-ethyl (18) chemistry is a series of 2,4,5,6-tetrasubstituted-phenyl pyrazoles 89 (Fig. 3.23) from Ishihara Sangyo Kaisha [96]. These compounds differ from previous phenyl pyrazoles in that they have substituents at the 6 position of the phenyl ring. Pre-emergence application of 89 provided 100% control at 63 g-a.i. ha of barnyardgrass, crab-grass, green foxtail, redroot pigweed, prickly sida, and velvetleaf Soybean was reported to have 20% injury for compound 89 at this rate of application. 

Not surprisingly, glyphosate absorption is also affected by species differences in cuticle structure and leaf morphology. Using the track sprayer method, foliar absorption of " C-glyphosate at field use rates with a flat fan nozzle ranged from 20 to 36% in velvetleaf, prickly sida, kochia and RR corn [10, 14]. These results indicated that studies on foliar absorption of glyphosate not only need to employ a relevant method (i.e., track sprayer) but also be conducted in the species of interest. 

Abstract This chapter describes the underlying criteria and assumption in the development and execution of field and associated laboratory bioassays. It provides details and commentary regarding the materials and methods used. More specifically, describes how glyphosate-desiccated wheat and other cover crops (crimson clover, subterranean clover, and rye) in no-till systems can directly and indirectly influence morningglory, pigweed, and prickly sida seedling emergence, with emphasis on the role of phenolic acids in plant residues and soil. 

Fig. 3.3 Weed seedlings in wheat plots at end of an experimental period (a) momingglory upper right comer and prickly sida center, and (b) pigweed center and momingglory lower left...

F. 3.13 Percent change in mean seedling numbers of momingglory (a), pigweed (b), and prickly sida (c) due to presence of desiccated cover crops for the 1992 and 1993 experimental periods in no-tiU Cecil A soil, where C equals crimson and S equals subterranean. Figures based on data from Blum et al. (1997). Henry A Wallace Institute for Alternative Agriculture Inc, data used with permission of Cambridge University Press... 

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