Guidelines for producing rice using furrow irrigation

"Original authors: Paul Tracy, Barry D. Sims, Steven G. Hefner and John P. Cairns""Missouri rice farmers started furrow-irrigated production beginning around 1990. For many years, the amount of land in "row rice" was small. But interest in the cropping system has increased in recent years. About 30% of the rice currently is produced with furrow irrigation. In felds well suited to fooded rice, furrow irrigation usually does not increase yields. Te main advantage of furrow-irrigated rice is that levees and gates are not required. Tis saves rice producers time and labor costs. Soils are an important factor in the decision process. For felds that do not efciently retain foodwater, furrow irrigation may be a good fit. Te purpose of this publication is to introduce producers to the furrow-irrigated rice system and help interested individuals decide whether that system has potential for use on their farms."--First page.Written by: Gene Stevens (Extension Professor, Agronomy), Johanna Nelson (Research/Lab Technician, Plant Sciences), Jim Heiser (Senior Research Associate, Plant Sciences)Revised 10/93, Revised 1/2

Rice Production with Furrow Irrigation in the Mississippi River Delta Region of the USA

Furrow irrigated rice is an alternative method for growing rice with less water and labor than conventional flood irrigation. In the Mississippi River Delta region, layflat plastic pipe is used to supply water to furrows from irrigation wells. Different size holes are punched in pipe to optimize uniformity of water distribution. Beds are made before planting to channel water down furrows. Rice seed is planted in rows with a grain drill. Water infiltration in furrows is two-dimensional through a wetted perimeter with soil in the bottom of furrows and sidewalls of beds. An ideal field for furrow irrigation has no more than 0.1% slope with high clay content. No rice cultivars have been developed specifically for furrow irrigation but tests showed that some cultivars tolerate water stress better than others. In field trials, rice yields with furrow irrigation were lower than flooded rice with the greatest yield loss in the upper part of fields. However, results indicated that rice yields can be increased with proper timing of nitrogen fertilization and irrigation and adaption of new rice herbicides for weed control

p21(WAF1) (/Cip1) limits senescence and acinar-to-ductal metaplasia formation during pancreatitis

Trans-differentiation of pancreatic acinar cells into ductal-like lesions, a process defined as acinar-to-ductal metaplasia (ADM) is observed in the course of organ regeneration following pancreatitis. In addition, ADM is found in association with pre-malignant PanIN lesions and correlates with an increased risk of pancreatic adenocarcinoma (PDAC). Human PDAC samples show down-regulation of p21(WAF1) (/Cip1) , a key regulator of cell cycle and cell differentiation. Here we investigated whether p21 down-regulation is implicated in controlling the early events of acinar cell trans-differentiation and ADM formation. p21-mediated regulation of ADM formation and regression was analyzed in vivo during the course of cerulein-induced pancreatitis using wild type (WT) and p21 deficient (p21(-/-) ) mice. Biochemical and immunohistochemical methods were used to evaluate disease progression over two weeks of the disease and during a recovery phase. We found that p21 was strongly up-regulated in WT acinar cells during pancreatitis, while it was absent in ADM areas, suggesting that p21 down-regulation is associated with ADM formation. In support of this hypothesis, p21(-/-) mice showed a significant increase in number and size of metaplasia. In addition, p21 over-expression in acinar cells reduced ADM formation in vitro, suggesting that the protein regulates the metaplastic transition in a cell-autonomous manner. p21(-/-) mice displayed increased expression and re-localization of β-catenin during both pancreatitis and subsequent recovery phase. Finally, loss of p21 was accompanied by increased DNA damage and development of senescence. Our findings are consistent with a gate-keeper role of p21 in acinar cells to limit senescence activation and ADM formation during pancreatic regeneration