Wide Range Of Maturities Research Articles

Effects of Some Qualitative Genes on Soybean Performance in Late‐Planted Environments

Researchers have suggested that cultivars adapted specifically to double‐crop environments should be developed. Little information is available concerning what plant traits are advantageous in these environments. Sets of near‐isogenic lines (isolines) of soybean [Glycine max (L.) Merr.] can be used to evaluate specific plant traits without the confounding effects of different genetic backgrounds. Isolines in ‘Harosoy’ and ‘Clark’ genetic backgrounds that possess genes controlling maturity and stem morphology were grown in conventional and in late‐planted environments at Urbana, IL in 1980, 1981, and 1982. The isolines tested provided a wide range of maturities and stem lengths, and produced wide differences in yield at both planting dates. Gene combinations that produced maturities of 96 to I01 d in the late environment were among the highest yielding in both environments. The Dt2 S gene combination, which conditions for semideterminate stem growth and shortened internodes, significantly increased yields in both environments in the later maturing backgrounds. Isoline ✕ planting date interactions were small and nonsignificant in the combined analysis over years. Thus, the genes tested conferred no more of a yield advantage in a late‐planted environment than they did in a conventional early‐planted environment. No evidence was found that any of these traits imparted specific adaptation to late planting. However, the improved performance in both planting times imparted by Dt2 and S is of interest.

Analysis of Alfalfa Root Carbohydrate Concentration by Near Infrared Reflectance Spectroscopy1

Near infrared reflectance spectroscopy (NIRS) has been used to evaluate forage plants primarily for their feeding quality. Our objective was to determine whether NIRS could also accurately measure the root total nonstructural carbohydrate (TNC) concentration of alfalfa (Medicago saliva L.) established by various methods and grown to a wide range of maturities in several environments. We assayed root TNC concentration of two alfalfa cultivars harvested by eight cutting schedules in each of 2 years after establishment and of one cultivar during the year of establishment with and without companion crops harvested at various small grain maturation stages within each of 2 years. Calibration equations for TNC concentration were obtained by multiple linear regression of conventional laboratory assay values on NIR spectra from 54 randomly selected samples using a scanning monochromator NIR spectro‐computer system. Calibration equations were verified with 18 additional samples selected from the original population. Five wavelengths were required to produce the best equation for TNC concentration analysis for each of the data treatments (log 1/R, first derivative, and second derivative). The squared coefficients of multiple determination (R2) of the three equations ranged from 0.98 to 0.99. The lowest standard error of analysis by NIRS of TNC concentration in verification samples was 1.17 dag kg−1 (%) dry weight for the log 1/R data treatment. We conclude that NIRS can analyze the TNC concentration of alfalfa roots more conveniently than, and as accurately as, conventional laboratory techniques and that accurate and precise analysis is not limited to a single mathematical treatment of the NIR data.

Storage Responses of Four Apple Cultivars to a “Rapid CA” Procedure in Commercial Controlled-atmosphere Facilities

Abstract Commercial applications of a “rapid CA” procedure (short loading time and rapid reduction of storage O2 to 2.5%) significantly improved retention of flesh firmness and juice acidity in controlled-atmosphere (CA)-stored apples from a wide range of production regimes. ‘Golden Delicious’ and ‘McIntosh’ apples responded more to the rapid CA procedure than did ‘Spartan’ or ‘Delicious’ apples. Rapid CA maintained fruit firmness of ‘Golden Delicious’ and ‘Spartan’ apples picked over a wide range of maturities and reduced the susceptibility of ‘Golden Delicious’ apples to bruising.

Influence of Cross-Sectional Shape of Raw Cotton on Dimensional Changes in Mercerization Without Tension

The relation of the cross-sectional shape of the raw fiber to the changes that occur upon mer cerization without tension was studied for a number of cotton varieties representing a wide range of maturities. Perimeters and diameters of fiber cross sections were measured by the use of an especially de signed instrument. Areas also were measured. It was found that the percent increase in area and the percent decrease in perimeter caused by loose mercerization are dependent upon the cross-sectional shape of the original raw fibers. Flat fibers shrank more in perimeter and increased more in area than did round fibers. This was partly explained as being due to a change toward circularity.