Salt tolerance of seven genotypes of zoysiagrass(Zoysia spp.)

Seven zoysiagrass genotypes were evaluated for salt tolerance in a greenhouse study.The plant materials included Zoysia matrella'Diamond',Z.japonica'Palisades',three Z.matrella×Z.japonica hybrids DALZ 1701,DALZ 1713,and'Innovation',and two Z.minima×Z.matrella hybrids(DALZ 1309 and'Lazer').Treatments included a control(nutrient solution)and two saline treatments representing moderate and high salt levels.The electrical conductivity(EC)was 1.3 dS m−1 for control and moderate(EC5)and high salinity(EC10)were 5.0 and 10.0 dS m−1,respectively.At the end of eight-weeks of treatment,the relative(percent control)shoot dry weight(DW)was greatest in'Diamond'in EC10,and the relative root DW was greatest in DALZ 1309 in EC5.A cluster analysis based on the relative tissue dry weight identified'Diamond',DALZ 1309,and DALZ 1713 as the most salt tolerant genotypes.Additionally,the green leaf area(GLA)index of'Diamond'and DALZ 1713 were 98.8%and 100%,respectively,indicating excellent visual appearance under high salt levels.Bi-weekly clipping DW showed that'Diamond'continued to produce biomass throughout the duration of the study under the EC10 treatment.Sodium(Na^(+))and chloride(Cl−)content in the shoot tissue of the seven turfgrass genotypes indicated that lower concentrations corresponded to greater salt tolerance indicating exclusion of Na+and Cl−from the shoot tissue.Taken together,the genotypes'Diamond'and DALZ 1713 were determined to be the most salt tolerant and recommended for use in areas with high soil or water salinity.

Effects of organic fertilizer with or without a microbial inoculant on the growth and quality of lettuce in an NFT hydroponic system

Organic food continues to increase in popularity worldwide.Similarly,hydroponic production of leafy greens is expanding globally and is an important component of the world's food supply.The purpose of this study was to evaluate the growth and quality of lettuce using six nutrient film technique(NFT)hydroponic systems.There were three treatments:organic fertilizer with or without a microbial inoculant and a conventional inorganic fertilizer as a control.The experiment was repeated over time.Results showed that the plants grown with organic fertilizer with additional microbial inoculant achieved similar shoot fresh and dry weight to those of the control,and dry weight was 17%higher than the organic fertilizer without inoculant.Nitrogen content in the shoot tissue of plants treated with organic fertilizer with inoculant was 10%and 24%greater than the control and the organic fertilizer without inoculant,respectively.However,when the organic fertilizer with inoculant was reused in a second experiment,shoot fresh and dry weight of plants in organic fertilizer with inoculant was lower than those in the control but were still higher compared to the organic fertilizer without inoculant.Additionally,electrical conductivity(EC)and pH of the organic fertilizer solutions fluctuated widely.Interestingly,relative chlorophyll content measured as SPAD and anthocyanin content in the leaf tissue increased in plants treated with organic fertilizer,regardless of inoculant,by 19%and 9%,respectively.