Onderzoek naar het voorkomen van gemeentelijke land- en tuinbouwbedrijven, het beslag dat deze bedrijven op landbouwgrond leggen en de mate waarin de particuliere agrarische producent concurrentie wordt aangedaan

The objectives of the diagnosis of bean production are to (1) contribute criteria for the design and completion of on-farm trials of the new bean technology and (2) to take information to research centers that helps define bean research priorities. A summary is presented of the methodology suggested and practiced in national and international courses on on-farm research carried out by CIAT's bean program.

The factors influencing the size and shape of exptl. field plots (area of exptl. lot, soil types, trial objective, no. of replicates, and degree of accuracy and homogeneity of the exptl. material) for the execution of field expt. are discussed. The basic principles of the following different methods to determine plot size are described: max. curve method, method of Koch and Rigney, Hatheway's method, and the max. curve method using the multiple linear regression model. Some considerations are presented on the border effect and on plot size in bush and climbing bean trials.

This issue of Unasylva focuses on the fortieth anniversary of FAO - -and, in particular, on 40 years of work by FAO's Forestry Department. Here, and in the two issues that follow, we will, in addition to publishing articles on important forestry topics, be reprinting selected excerpts from early issues of Unasylva. This issue, for example, includes the major portion of an article from the very first Unasylva: "The disappearance of the tropical forests of Africa,'' by Andr Marie A.