TERRY COUNTY AG NEWS June 25, 2013 — Cotton th 209 South 5 Street Brownfield, TX 79316 Chris Bishop, Terry Co. CEA-AG Phone: 806-637-4060 Fax: 806-637-2588 http://terry-tx.tamu.edu/ Cotton Agronomy Crop Update received some moisture following dry planting Recent storms have provided much needed and were beginning to emerge. With high tem- moisture across much of the High Plains peratures forecast in the 90s for the next ten and parts of the Panhandle. Unfortunately, days and only slight chances for additional these storms also brought hail and high rainfall, cotton crops that have begun squar- winds that have caused varying levels of ing should be watched closely for moisture damage to already delayed cotton crops. stress, especially in areas where little rainfall Some fields were completely destroyed in was experienced during the recent storm the areas where large amounts of hail events. and/or high winds were observed. Cur- rently, there is no hard number to report in Plant Growth Regulators terms of lost cotton crops. Reports from Questions concerning mepiquat-based (Pix, Texas A&M AgriLife County Extension Ag Pix Plus, Mepex, Mepichlor, Mepiquat Chlo- Agents and IPM Agents indicate that some ride, Mepex GinOut, Stance, and others) plant fields have already been replanted to cotton growth regulators (PGRs) are being asked. or sorghum. Rainfall amounts reported by Mepiquat chloride (MC) reduces production of the Texas Tech University West Texas gibberellic acid in plant cells that in turn re- Mesonet System vary greatly thus far for duces cell expansion, ultimately resulting in the month of June and range from a high of shorter internode length. MC will not help the 5.13” to a low of 0.93” for Anton and Friona, plants compensate for earlier weather or dis- respectively. These amounts have provided ease damage by increasing growth rate. It enough moisture to germinate cotton may, under good growing conditions, increase planted to dryland production fields in some fruit retention, control growth and promote areas but more is needed at timely intervals earliness. MC should not be applied if crop is to maintain established stands. Based on under any stresses including moisture; heat; data from the CottonHeatUnits.com web- severe spider mite, insect, or nematode dam- site, heat unit accumulations at Lubbock age; disease stress; herbicide injury; or fertil- total 699 DD60s, which is 95 above our long ity stress. Results from our replicated testing term average of 604. In general, the cotton indicates that we observed from 5 to 20% re- stands that have been established and man- duction in plant height (compared to the con- aged to dodge the weather bullet appear to trol) from 16 oz of 4.2% a.i. MC material ap- be in fair to good condition. Growth stages plied in up to 4 sequential 4-oz/acre applica- of these crops range from just emerged or tions starting at match head square (MHS) emerging to very early squaring. During my and ending at early bloom. We have been able travels to the eastern part of the region ear- to "shave" about 1 node from the growth of the lier last week I determined that two dry- main stem at some locations, which can result land variety trial locations we planted had Continued on page 2 Educational programes conducted by the Texas A&M AgriLIFE Extension serves people of all ages regardless of socioeconomic level, race, color, sex, religion, disability or national origin. The Texas A&M University System, the United States Department of Agriculture, and the County Commissioners Courts of Texas cooperating. Continued from page 1 Pentia Consistent yield increases Mepiquat pentaborate mole- have not been observed from Plant Growth Regulators cule (different from MC) any of the MC materials we 9.6% a.i./gallon or 0.82 have investigated. A good in about 3-5 days earlier cut- lb/gallon a.i. fruit load will normally help out. Low rate multiple ap- control plant growth. Fields plications beginning at Mepex Gin Out with poor early-season fruit MHS have generally pro- 4.2% a.i./gallon or 0.35 retention, excellent soil mois- vided more growth control lb/gallon a.i. with 0.0025% Ki- ture, and high nitrogen fertil- than higher rate applica- netin (a cytokinin). ity status may be candidates tions made at first bloom Cytokinins are plant hor- for poor vegetative/fruiting or later. mones that promote cell divi- balance and should be sion and growth and delay the watched carefully. Our results have shown that senescence of leaves. This we usually do not get statisti- product has use guidelines Growers who have planted cally significant increases in similar to other MC materials. varieties with vigorous yields, but do get excellent growth potential and have growth control. Many times Stance fields with excellent growing we don't see a lot of differ- Bayer CropScience's Stance conditions need to be con- ences in performance of these product is a mepiquat chloride cerned. For brush roll header products when comes to based PGR. It is a 4 to 1 ratio stripper harvest, 28-32 inch growth control. of mepiquat chloride and cy- tall plants optimize stripper- clanilide (0.736 lbs/gallon me- harvesting efficiency. If possi- Mepiquat chloride (MC) piquat chloride plus 0.184 ble, target a maximum plant based products have been lbs/gallon cyclanilide). Cy- size of about 32 inches for cot- around for many years. Sev- clanilide is an auxin synthesis ton plants under high input eral plant growth regulators and transport inhibitor. Aux- irrigation (drip or high capac- (PGRs) based on the same ac- ins are generally referred to as ity pivots). If plants get larger tive ingredient are now avail- compounds which have the ca- than 36 inches, harvest effi- able. Pentia is a formulation pacity to induce cell elonga- ciency and productivity drop of mepiquat pentaborate - a tion. The inhibition of auxins significantly. With some spin- different molecular structure could reduce cell elongation dle picker harvesters working than MC. Mepex Gin Out and inhibit growth. Produc- in the region, plant size for contains the same amount of ers should be aware that high yielding cotton is not as MC active ingredient as oth- the mepiquat chloride con- much of a harvesting consid- ers, but contains an addi- centration in Stance is eration. Pickers can handle tional PGR. Refer to the prod- about twice as high as most higher yielding, taller uct labels or contact local rep- of the other materials we plants with much greater resentatives to ensure you have become accustomed ease than stripper har- understand the correct use of to applying. THEREFORE vesters, especially when these products. THERE IS A CORRE- the stalks are still alive (or SPONDING REDUCED “green”). However, if Mepex, Mepichlor, Mepiquat RATE. If you have specific weather constraints at Chloride and other generics questions concerning this harvest time delay har- 4.2% active ingredient (a.i.)/ product, visit with your local vesting after freezing gallon or 0.35 lb/gallon a.i. Bayer CropScience rep. weather, the large brittle The articles in this newsletter were published in a recent issue of FOCUS on South Plains Agriculture, a newsletter from the Lubbock Research and Extension Center. http://lubbock.tamu.edu/focus. FOCUS Editor—Patrick Porter 2 plants can still result in temperatures, southwest fall conditions are encoun- picker harvesting difficul- winds at 30 mph at 10% rela- tered. The situation that has ties. tive humidity? If so, those arisen due to the release and conditions will limit plant availability of new genetics is Determination of application growth in many fields with challenging. Visit with your rates is generally more "art" low irrigation capacity. seed company representative than "science" for these prod- to determine which new va- ucts. Applications should be- Watch high growth potential rieties should be watched gin when 50% of the plants varieties and fruit retention. closely for MC needs under have one or more matchhead If a high growth potential va- field-specific conditions. Se- squares (see specific product riety has been planted and quential applications can be label for more information). It has encountered low fruit re- adjusted to meet subsequent is best to get a handle on ex- tention, then MC rate should crop conditions and growth cessive growth potential early be increased, especially under potential. For any questions if conditions favor excessive high water, fertility, and good concerning this information, growth for an extended period growth conditions. One producers are welcome to con- of time. Herein lies the High should target applications to tact Mark Kelley at 806-781- Plains dilemma: It is un- fields with high growth po- 6572 (mob), or 806-746-6101. known at that time as to how tential. Some newer varieties weather will affect the crop in may need aggressive manage- Mark Kelly July and on into early Au- ment under high irrigation Extension Agronomist gust. Will we get 100+ degree capacity and/or if heavy rain- Cotton Disease Update Root-knot Nematode roots. These symptoms often reproduction of the nematode Despite the rainfall that has resemble nutrient deficien- and adversely affecting plant been received the past few cies, which arise from dam- growth. Such feeding activity weeks, dry conditions con- age that occurs to plant roots in conjunction with reproduc- tinue to be experienced and rendering them unfit for ac- tion of the nematode is re- the crop is off to a relatively quiring water and/or nutri- sponsible for the develop- slow start to this growing ents. The feeding conducted ment of the galls mentioned season.