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experimental (experimental ones are designated CG followed by a number). Diverse findings Details of the scientific procedures, as well as charts and graphs showing the responses of various rootstocks, are in their paper in the Fruit Quarterly. Here are some of their findings relating to the commercially available rootstocks: • Vegetative tree growth was much stronger in clay than the sandy soil, as expected. However, some rootstocks (B.9, G.214, G.890) appear to grow similarly in both soils. • Some rootstocks, including B.9, and B.396, appeared tolerant to replant disease in clay, but sensitive in sandy soil. Other rootstocks, including G.16, appeared to have the opposite relationship. • Rootstocks exhibited distinct patterns of growth as influenced by soil pH. G.41 and MM.111 had optimum growth at pH 7.5 (mildly alkaline). G.41 may be well adapted to higher pH soils. • Scion leaf concentration of different micro- and macronutrients differed for different rootstocks. • G.41 seemed to have higher phospho- rus concentrations than most root- stocks at the various pH levels. MM.111 reached optimal values in more alkaline conditions, while leaf phosphorus content of G.969 was the highest at the acidic pH of 4.5. • The effect of soil pH on leaf calcium concentration followed very different patterns among rootstocks. G.41 had a low concentration in the midrange pH and higher concentration at the extremes, while MM.111, like most rootstocks, showed an increasing level of calcium with increasing pH. "High calcium concentration is very important to prevent different fruit phys- iological disorders like bitter pit, scald, etc.," the researchers wrote. The highest calcium concentration was found in apple leaves grown on G.969 in the wide range of pH 5.5 to pH 8.5. G.41 had high leaf calcium at pH 8.5 but lower calcium at the more neutral pH of 6.5. Calcium content of MM.111 was very low at low pH and increased linearly to a high level at pH 8.5. "The interaction of soil pH and root- stock genotype means that the same root- stock will not be the best for different soil pHs. It appears that certain rootstock genotypes will perform better in high pH soils while other rootstocks will perform better in low or neutral pH soils," the researchers said. "As we develop more information on rootstock uptake of nutrients in different pH soils, it will allow fruit growers to select a rootstock that is adapted to their soil pH to improve calcium and iron uptake to reduce bitter pit and chlorosis problems in the field." Scratched the surface The studies showed that rootstocks don't behave the same way in different soil environments (pH, soil type, and www.goodfruit.com replant disease), Fazio said. As a breeder, he was excited to know that these are genetic variations that can be bred for. In the process of the studies, they found a genetic marker for locations of genes that regulate sodium and potas- sium uptake. Sodium is related to salty, alkaline soils and potassium is related to fruit size, he said, so these genes are important for breeding. "We have just scratched the surface with the results of these experiments," the researchers wrote. "The absorption of soil nutrients once thought to follow similar trends in all apple rootstocks does not behave the same way in newer rootstocks." In the short term, growers can use this new knowledge in choosing rootstocks for specific sites. Growers on the sandy soils 0%for of northern Michigan will want to take a close look at G.87 or G.214. Western grow- ers with alkaline soils will want to look closely at G.41, Fazio said. In the longer term, breeders may be able to tailor rootstocks to sites or other specific needs, like efficiency of fertilizer use, waste and runoff of phosphorus, and the nutrient content of apples. • 0%INTEREST 48 MONTHS CK OR CHOOSE CASH BACK! On T4000 S T4000 Series in stock TD4040F The Ready to Roll Sales Event is in full swing, and that means you can get 0% financing for 48 months or cash back on select New Holland tractors: T4000V and T4000F Series Tractors (62 to 82 PTO hp) Get Ready to Roll now with outstanding deals! Program ends Stop by today, or visit www.newholland.com/na for complete details. BIN TRAILERS AS LOW AS. . . $4,650 RENTAL RETURN TD4050F with Cab QUINCY OTHELLO MOSES LAKE PASCO WALLA WALLA HERMISTON LA GRANDE participating New Holland dealers in United States. Offer subject to change. Taxes, freight, set-up, delivery, additional options or attachments not included in price. ©2012 CNH America LLC rights reserved. New Holland and CNH Capital are registered trademarks of CNH America LLC. *For agricultural use. Offer subject to CNH Capital America LLC credit approval. See your New Holland dealer for details and eligibility requirements. Depending on model, a down payment may be required. Offer good through June 30, 2012, at GOOD FRUIT GROWER MAY 1, 2012 29 T4040V with Low Prof ile Saf-T Cab