| Beckmannia syzigachne (Steud.) Fern. | MAKS2407, MAKS2408 |
| Begonia evansiana Andr. | MAKS0485, MAKS2064 |
| Belamcanda chinensis (L.) DC. | MAKS0763 |
| Benincasa cerifera Savi | MAKS0368 |
| Berchemia lineata (L.) DC. | MAKS0278, MAKS1205 |
| Berchemia racemosa Siebold et Zucc. | MAKS0280, MAKS1204 |
| Beta vulgaris L. | MAKS1413 |
| Betula corylifolia Regel ex Maxim. | MAKS1608 |
| Betula ermanii Cham. | MAKS1731 |
| Betula grossa Siebold et Zucc. | MAKS1727, MAKS1728, MAKS1860 |
| Betula maximowicziana Regel | MAKS1729 |
| Betula platyphylla Sukatchev var. japonica (Miq.) Hara | MAKS1730, MAKS0726 |
| Bidens biternata (Lour.) Merr. et Sherff | MAKS0438, MAKS0588 |
| Bidens tripartita L. | MAKS1358 |
| Bistorta major S. F. Gray var. japonica Hara | MAKS0482, MAKS0665, MAKS0667 |
| Bistorta tenuicaulis (Bisset et Moore) Nakai | MAKS1510, MAKS0668 |
| Bletilla striata (Thunb.) Reichb. fil. | MAKS0759 |
| Boehmeria biloba Wedd. | MAKS1674 |
| Boehmeria longispica Steud. | MAKS1649, MAKS1654, MAKS1781 |
| Boehmeria nipononivea Koidz. | MAKS0715 |
| Boehmeria platanifolia Franch. et Savat. | MAKS1652 |
| Boehmeria sieboldiana Blume | MAKS1780 |
| Boehmeria sp. | MAKS1653 |
| Boehmeria spicata (Thunb.) Thunb. | MAKS1650, MAKS1651, MAKS1779 |
| Boenninghausenia albiflora (Hook.) Reich. var. japonica (Siebold) S. Suzuki | MAKS1228 |
| Bothriochloa sp. | MAKS2415 |
| Brassica campestris L. | MAKS0107 |
| Brassica midsuna Siebold | MAKS0105 |
| Brassica oleracea L. | MAKS0106 |
| Bredia hirsuta Bl. | MAKS0422, MAKS2085 |
| Briza minor L. | MAKS2405, MAKS2406 |
| Bromus japonicus Thunb. | MAKS2402 |
| Bromus pauciflorus (Thunb.) Hack. | MAKS2456 |
| Bromus sp. | MAKS2401 |
| Broussonetia kazinoki Siebold | MAKS1658, MAKS1659, MAKS1660, MAKS0705 |
| Broussonetia papyrifera (L.) Vent. | MAKS1631, MAKS1661, MAKS1662, MAKS0704 |
| Broussonetia sp. | MAKS1657 |
| Buckleya lanceolata (Siebold et Zucc.) Miq. | MAKS1549, MAKS1550, MAKS0683 |
| Bupleurum longeradiatum Turcz. subsp. sachalinense (Fr. Schm.) Kitag. var. elatius Kitag. | MAKS2042 |
| Bupleurum scorzoneraefolium Willd. var. stenophyllum Nakai | MAKS2043 |
| Buxus liukiuensis Makino | MAKS0738 |
| Buxus microphylla Siebold et Zucc. | MAKS1573 |
| Buxus microphylla Siebold et Zucc. var. japonica (Muell. Arg. ex Miq.) Rehder et Wils. | MAKS1574 |
