Effects of Cropping System (Organic and Conventional) on the Fiber Quality Index, Spinning Consistency Index and Multiplicative Analytic Hierarchy Process of Cotton (Gossypium hirsutum L.)

Markets for organically produced high quality cotton (Gossypium hirsutum L.) are projected to increase. Field experiments were conducted in Palamas, Karditsa in Central Greece, to compare the effects of two cropping systems on fiber quality of three cotton cultivars. The experiments, conducted during three years, were laid out in a split plot design with four replicates, two main plots (organic and conventional system) and three sub-plots (cotton cultivars). Findings suggest that fiber quality index (FQI), spinning consistency index (SCI) and multiplicative analytic hierarchy process (MAHP) are three indices that could be integrated in a useful protocol for the evaluation of different cropping systems for cotton cultivation. In particular, our results indicate that in general there was not any superiority of conventional compared to the organic cropping system regarding fiber quality as shown by the above mentioned indices. Regarding the length of the cotton fiber, this was positively correlated with micronair and the uniformity index of the cotton fiber. The organic system resulted to higher values of SCI than the ones of the conventional (1547.9 and 1522.3, respectively). The present 3-years study shows that organic cultivation of cotton can ensure high fiber quality and this was clearly confirmed by means of the several important indices

Effects of cropping system (organic and conventional) on the fiber quality index, spinning consistency index and multiplicative analytic hierarchy process of cotton (Gossypium hirsutum L.)

Markets for organically produced high quality cotton (Gossypium hirsutum L.) are projected to increase. Field experiments were conducted in Palamas, Karditsa in Central Greece, to compare the effects of two cropping systems on fiber quality of three cotton cultivars. The experiments, conducted during three years, were laid out in a split plot design with four replicates, two main plots (organic and conventional system) and three sub-plots (cotton cultivars). Findings suggest that fiber quality index (FQI), spinning consistency index (SCI) and multiplicative analytic hierarchy process (MAHP) are three indices that could be integrated in a useful protocol for the evaluation of different cropping systems for cotton cultivation. In particular, our results indicate that in general there was not any superiority of conventional compared to the organic cropping system regarding fiber quality as shown by the above mentioned indices. Regarding the length of the cotton fiber, this was positively correlated with micronair and the uniformity index of the cotton fiber. The organic system resulted to higher values of SCI than the ones of the conventional (1547.9 and 1522.3, respectively). The present 3-years study shows that organic cultivation of cotton can ensure high fiber quality and this was clearly confirmed by means of the several important indices

Arbuscular Mycorrhizal Fungi: A Blessing or A Curse for Weed Management in Organic Olive Crops?

Arbuscular Mycorrhizal (AM) fungi form symbiotic associations with the roots of many plants including important weeds. Cultural practices affect the populations and the infectivity of AM fungi. Density, biomass, root density, AM root colonization and N% of weeds were compared in the two olive production systems (organic and conventional). Weed species differed in the response to AM root colonization. The highest AM root colonization was found for Lactuca serriola, Picris echioides, Plantago lanceolata and Gallium aparine. In addition, Avena sterilis, Fumaria officinalis and Stellaria media had the lowest AM root colonization. The highest AM root colonization of weeds was found in organic olive fields. AM root colonisation of weeds influences the density and biomass of competitive weeds. A positive correlation was found between AM root colonization and weed growth. Moreover, the different cultural practices in two production systems influence the weed AM root colonization. There were significant differences in the density and biomass of competitive weeds (Avena sterilis L.; Galium aparine L.; Lactuca serriola L.; Picris echioides L.; Plantago lanceolata L.; Sonchus oleraceus L.), with the highest values being found in organic olive fields. On contrast, there were no significant differences between the organic and conventional systems in the density and biomass of non-competitive weeds (Anthemis arvensis L.; Fumaria officinalis L.; Lamium aplexicaule L.; Lolium rigidum Gaudin.; Stellaria media (L.) Vill.; Veronica hederifolia L). Our results indicate that organic cultural practices significantly increased weed biomass and AM root colonization. The mycorrhizal symbiosis is an important factor influencing weed growth

Weed populations are affected by tillage systems and fertilization practices in organic flax (Linum usitatissimum L.) crop

Flax is a weak competitor against weeds. To obtain high yield of flax, good weed management practices must be implemented. Field experiments were conducted during 2009 and 2010 to determine the effects of tillage systems and fertilization on weed flora in organic flax crop (Linum usitatissimum L.). The experiments were laid out in a split-plot design with four replicates having three main plots (conventional tillage: CT, minimum tillage: MT and no-tillage: NT) and three sub-plots (compost, vetch and faba bean as green manure). The total weed densities were significantly different among the tillage systems. In NT plots, the presence of wheat residues clearly reduced weed number. Crop residues mainly affect light interception, temperature and moisture of the soil. Differences in nitrogen availability of the fertilizers had a large effect on weed density and biomass. The lowest weed density was found in compost plots. Moreover, the highest density of competitive weeds (Amaranthus retroflexus, Chenopodium album, Convolvulus arvensis, Cynodon dactylon, Cyperus rotundus, Datura stramonium, Setaria verticillata, Sinapis arvensis and Solanum nigrum) was found under MT and CT systems, while the lowest was found in NT plots. In addition, concerning the density of noncompetitive weeds, there were no significant differences among the tillage systems. Moreover, there were no significant differences in the density of non-competitive weeds between the organic fertilization treatments. No-tillage and low nitrogen fertilization appeared to contribute to the suppression of weeds

Performance of Wheat Varieties (Triticum aestivum L.) under Conservation Tillage Practices in Organic Agriculture

Field experiments were conducted to determine the effects of tillage systems and varieties on growth, yield and quality of wheat crop (Triticum aestivum L.). The experiments conducted at two sites were laid out in a split-plot design with four replicates, three main plots [conventional tillage (CT), no-tillage (NT) and minimum tillage (MT)] and four sub-plots ('Siette', 'Panifor', 'Myrto', 'Estero'). The soil porosity and total nitrogen were higher in soils subjected to conservation tillage systems (NT and MT) than under conventional tillage. There were no differences in root growth neither between the tillage systems nor among the varieties. Yield was influenced by the tillage system and variety The highest grain yield (421-459 kg ha(-1)) was found under the CT system with 'Siette', 'Myrto' and 'Estero' varieties. In contrast, the highest grain yield was observed under conservation tillage (NT and MT) with 'Panifor' variety. There were no significant differences between the tillage systems concerning the protein content and Zeleny value. In contrast, the highest Hagberg falling number was found with MT Zeleny value was positively and significantly correlated with protein content. High flour quality, as demonstrated by high protein content and Zeleny value, and low Hagberg falling number, was produced in the 'Estero' variety

Weed-suppressive effects of maize-legume intercropping in organic farming

In organic agriculture, intercropping is receiving increasing attention as it offers potential advantages for increasing sustainability in crop production. However, intercropping can increase competition between crops and weeds. In this study, we analyzed the effects of maize-legume intercrops on the weed community in an organic cropping system. We were concerned only with competition between crops and weeds for light. We recorded a statistically significant negative correlation between the fraction of photosynthetically active radiation (Fint PAR) intercepted by the canopy, and both weed density and weed dry matter. Maize-legume intercropping led to a higher soil canopy cover (leaf area index) than sole crops. The lowest values for Fint PAR were received in sole crops. Thus, in maize-legume intercrops the decrease in available light for weeds led to a reduction of weed density and dry matter, compared to sole crops. Intercropping maize and legumes considerably reduced the weed density in the intercrop compared with the maize pure stand. Weed suppression by crops was also greater on a low-productivity site than on a high-productivity site. Our results indicate that intercropping could be useful for weed suppression in organic row-crops such as maize and cotton. © 2010 Taylor & Francis

Response of organic linseed (Linum usitatissimum L.) to the combination of tillage systems, (minimum, conventional and no-tillage) and fertilization practices: Seed and oil yield production

Abstract Limited tillage systems, especially no-tillage, have become widespread in recent years. The no-tillage practice is widely adopted worldwide for erosion control and to maintain soil fertility. Field experiments were conducted to determine the effects of tillage systems and organic fertilization on the growth, yield and oil content of flax crop (Linum usitatissimum L.). The experiments, conducted during 2009 and 2010, were laid out in a split plot design with four replicates, three main plots (conventional tillage, minimum tillage and no-tillage) and the three sub-plots (compost, vetch and faba bean as green manure). The soil organic matter and total nitrogen were higher in soils subjected to conservation tillage systems (minimum and no-tillage) than under conventional tillage. The highest leaf area index (LAI), dry weight and arbuscular mycorrhizal (AM) root colonization was found in conservation tillage systems. There were no significant differences between the organic fertilization treatments concerning the LAI, dry weight and AM root colonization. There were significant differences for root growth between the tillage systems. The highest root weight was found in the no-tillage system. Moreover, the highest seed yield (1761 kg ha -1 ) and oil yield (670 kg ha -1 ) were found with minimum tillage. There were statistically significant differences between minimum tillage and conventional tillage. Vetch and faba bean green manures had a significant effect on oil content. A high correlation was observed between oil yield and oil content. Our results indicated that conservation tillage systems enhance organic matter in soils and increase oil yield of flax

Effects of aluminum and moisture levels on aluminum bioaccumulation and protein content in the earthworm Octodrilus complanatus

Laboratory experiments were conducted to determine the effects of soil aluminum levels and moisture content on aluminum (Al) bioaccumulation and protein content in the earthworm (Octodrilus complanatus). The experimental design was a completely randomized block with 2 factors (aluminum content [C-0: 0 mg kg(-1), C-1: 1000 mg kg-1, C-2: 2000 mg kg(-1), C-3: 3000 mg kg(-1)] and moisture level [M1: 100% of soil water capacity, M2: 60% of soil water capacity] and 3 replications. The lowest pH was noted in the C-0 treatment. There were no significant differences in the electrical conductivity, cation exchange capacity or total nitrogen in soil between the aluminum treatments. Moreover, there were no significant differences in soil properties between the moisture treatments. The highest soil Al content was noted in the C-3 treatment. No earthworm mortality was observed in soil contaminated with Al. Moreover, the highest aluminum content in earthworms was observed in the C-3 treatment. The aluminum content in the earthworms was significantly positively correlated with the aluminum content in the soil (r=0.984***, p<0.001). Our results indicated that the growth of earthworms was affected by the Al level. Lastly, Al caused a reduction in earthworm protein content